relational aggression in adolescents' sibling relationships: links to sibling and...

Relational Aggression in Adolescents' Sibling Relationships: Links to Sibling and Parent-Adolescent Relationship QualityAuthor(s): Kimberly A. Updegraff, Shawna M. Thayer, Shawn D. Whiteman, Donna J. Denningand Susan M. McHaleSource: Family Relations, Vol. 54, No. 3 (Jul., 2005), pp. 373-385Published by: National Council on Family RelationsStable URL: http://www.jstor.org/stable/40005291 .

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Relational Aggression in

Adolescents' Sibling Relationships: Links to Sibling and

Parent- Adolescent Relationship Quality*

Kimberly A. Updegraff Shawna M. Thayer Shawn D. Whiteman Donna J. Denning Susan M. McHale**

Family Relations, 54 Quly 2005), 373-385. Blackwell Publishing. Printed in the USA. Copyright 2005 by the National Council on Family Relations.

Abstract: This study examined the links between sibling relational aggression and other sibling relationship qualities (i.e., intimacy, negativity, and temporal involvement) and broader parenting dynamics. Participants included 185 adolescent sibling pairs and their mothers and fathers. Data were gathered during home interviews and a series of

nightly phone calls with adolescents and parents. Findings revealed that sibling relational aggression was related to

sibling intimacy and negativity. In addition, connections emerged between relational aggression and qualities of the

parent-child relationship, parents' differential treatment, and parents' strategies for handling sibling conflict.

Key Words: adolescence, parent-adolescent relationships, relational aggression, siblings.

Sisters and brothers play central roles in children's lives and in shaping family dynamics. The majority of families in U.S. society today include at least two children (Eggebeen, 1992), and by middle childhood, children spend more time with their siblings than in any other social context (McHale & Crouter, 1996). The nature of children's interactions with their siblings is linked to their psycho- social adjustment, to the quality of parent-child relationships, and to parental stress. Warm and supportive relationships with siblings are associated

with peer acceptance and competence in middle childhood (e.g., Stormshak, Bellanti, & Bierman, 1996) and supportive friendships in adolescence (e.g., Updegraff, McHale, & Crouter, 2002). In contrast, sibling conflict predicts unique variance in children's antisocial behavior, even after accounting for parent-child relationship experiences (e.g., Bank & Burraston, 2001). Sibling conflict and negativity also may elevate parental stress (Patterson, 1986).

Most research has focused on the correlates of warmth/support and conflict or physical aggression

*We are grateful to the families and youth who participated in this project. We thank Ella Bashore, Matthew Bumpus, Devon Corneal, Heather Helms, Julia Jackson-Newsom,

Mary Maguire, Joseph Novotny, Robert Smith, Jennifer Tanner, and Corinna Jenkins Tucker for their assistance in conducting this investigation and Ann Crouter for her valuable comments on this manuscript. Portions of this paper were presented at the biennial meeting of the Society for Research in Child Development, Tampa, FL, April 2003. Funding was provided by National Institute of Child Health and Human Development grant R01HD29409-01A3 (Ann C. Crouter and Susan M. McHale, coprincipal investigators).

**Kimberly A. Updegraff is an Associate Professor in at the Department of Family and Human Development, P.O. Box 872502, Arizona State University, Tempe, AZ

85287-2502 ([email protected]). Shawna M. Thayer is a doctoral candidate at the Arizona State University. Shawn D. Whiteman is an Assistant Professor in the Department of Child Development and Family Studies at Purdue University. Donna J. Denning is a Psychometric Analyst with Aries Technology. Susan M. McHale is a Professor in the Department of Human Development and Family Studies at the Pennsylvania State University.



374 Family Relations • Volume 54, Number 3 • July 2005

between siblings. The present study is designed to extend the understanding of sibling relationships in adolescence by exploring how siblings' experiences of relational aggression are connected to other qualities of the sibling relationship and broader parenting dynamics. Relational aggression, or behaviors that are intended to harm others' social relationships, has received attention in the context of peer group interactions (e.g., Cairns, Cairns, Neckerman, & Ferguson, 1989; Crick & Grotpeter, 1995, 1996). Specifically, relational aggression encompasses girls' and boys' efforts to damage others' social relationships through behaviors such as social alienation and exclusion, tell- ing secrets and spreading rumors, and withholding support and acceptance (Cairns et al.; Crick & Grotpeter, 1995, 1996). Recently, researchers have suggested the importance of exploring relational aggression in other social contexts, such as romantic relationships, friendships, and sibling relationships (Crick et al., 2001). Given that negative affect is a common part of sibling relationships (Dunn, 1993), relational aggression may be particularly important to consider in this relationship context. A study of 50 sibling pairs in middle childhood revealed that siblings reported using relationally aggressive strategies more often than both verbal and physical aggression (Crick et al.; O'Brien, 1999).

There are a number of reasons to study relational aggression in the sibling relationship and within the broader family context. First, social learning princi- ples suggest that siblings provide each other with opportunities to learn interpersonal behaviors and skills that may carry over to peer interactions. Ex-

ploring relational aggression between siblings may provide insights about potential antecedents of peer relational aggression. Second, naturally occurring differences across families in the sex constellation of the sibling dyad allow for comparisons of relationally aggressive behaviors in same- versus mixed-sex dyads. Given the extent of gender segregation in the peer group in childhood and early adolescence (Ruble & Martin, 1998), sibling relationships offer a unique opportunity to explore the role of gender in relational aggression. Finally, relational and social forms of aggression have been identified as a major concern for parents (Underwood, 2003), particularly parents of teenage girls, and have received considerable attention in the media (e.g., "Meet the GAMMA Girls," 2002). Thus, information that can lead to the development of intervention programs with a family component may be beneficial.

Links Between Sibling Relational

Aggression and Other Qualities of the Sibling Relationship

Our first goal was to explore how sibling relational

aggression was related to other qualities of firstborn and second-born adolescents' sibling relationships, including intimacy, negativity, and temporal involvement. Information about the connections between relational aggression and both positive and

negative dimensions of adolescents' sibling relation-

ships could potentially provide insights about the

relationship context in which relational aggression occurs. Perspectives on social development highlight adolescence as a time when the formation of close

reciprocal relationships with other youth is an

important developmental task (Sullivan, 1953). Studies of girls' and boys' social networks indicate that siblings, as well as friends, can fulfill roles in adolescents' lives as sources of support (e.g., Buhrmester, 1992). Given the developmental significance of social connections with other youth, we

anticipated that siblings' efforts to harm the other's social relationships would be linked to lower levels of intimacy and involvement and higher levels of

negativity in adolescents' sibling relationships. We also expected that relational aggression would be more harmful to girls' than to boys' sibling relation-

ships, a pattern that is suggested by girls' greater ori- entation toward interpersonal relationships (Ruble & Martin, 1998) and by studies of peer relational

aggression (e.g., Crick & Grotpeter, 1995). Sibling and peer relationships differ in ways that

may have implications for the links between relational aggression and other relationship qualities. First, sibling relationships typically include individu- als who differ in power or status and in the roles they assume. Younger siblings are more likely to model their older siblings (e.g., McHale, Updegraff, Helms- Erikson, & Crouter, 2001) and to place greater value on the relationship than are their older siblings (Buhrmester, 1992). Thus, we expected that relational aggression would be more strongly linked to the qualities of the sibling relationship for younger than for older siblings. Second, an important contri- bution of this study was its exploration of the links between relational aggression and sibling relationship quality for same- versus mixed-sex sibling pairs. Maccoby (1998) proposed that one consequence of



Sibling Relational Aggression • Updegrajf et al. 375

gender segregation in early and middle childhood is that boys and girls learn different strategies for inter- acting in social groups and handling disagreements. Boys are more concerned with dominance and status and more likely to settle disagreements through overt and physical aggression, whereas girls use different forms of discourse and are more likely to handle disagreements with peers via conflict-minimizing strate-

gies and relational aggression (Maccoby, 1998). These differences in girls' and boys' socialization experiences and exposure to relational aggression lead us to explore the possibility that relational aggression is differentially linked to relationship qualities in same- versus mixed-sex sibling pairs. Given the greater emphasis girls place on relationships (Ruble & Martin, 1998), relational aggression may be linked to more negative relationship experiences for sisters.

Sibling Relational Aggression and Parenting

Our second goal involved examining how relational

aggression was linked to parenting dynamics. We drew upon Parke and Buriel's (1998) model of parenting, which distinguishes between parents' direct and indirect influences on their children's relation-

ships. Indirect influences, such as those described by social learning theory, suggest that parents have an impact on their children's social relationships through the more general influence of parent-child relationship quality on children's social development (e.g., MacDonald & Parke, 1984). Parents' direct influences, in contrast, refer to parents' efforts to

guide their offspring's relationship experiences and include the strategies parents use to intervene in sib-

ling conflicts and their efforts to encourage siblings to spend time together (e.g., McHale, Updegraff, Tucker, & Crouter, 2000).

Indirect Parental Influences

To study how the general quality of the parent-child relationship was linked to siblings' relational aggression, we focused on two relationship dimensions, parental warmth and involvement. We assessed sib-

lings' experiences with both mothers and fathers and examined each sibling's dyadic relationship experiences with his or her parents as well as parents' differential treatment (PDT) of the two siblings in the domains of warmth and involvement.

Beginning with parenting of each sibling as an individual, evidence of links between parent-child and child-sibling relationships has emerged in a number of studies: Consistent with social learning tenets, positivity in the parent-child relationship is associated with more positive and less negative sibling relationships (e.g., Stocker & McHale, 1992). However, when mother-child and father-child relationships both have been studied as potential correlates of sibling relationships, some research has found that father-child experiences are more closely linked to the nature of sibling exchanges (e.g., Stocker & McHale, 1992). Mothers and fathers tend to adopt different roles with their children, with mothers focusing on caregiving and fathers on play and leisure (Parke & Buriel, 1998). Experiences with fathers may be more strongly linked to sibling relationship characteristics to the extent that siblings are leisure oriented rather than care oriented. Further, maternal roles tend to be more scripted than those of fathers, and the greater variability in paternal roles may engender stronger links with a range of youth "outcomes" including sibling relationship qualities (Crouter, Helms-Erikson, Updegraff, & McHale, 1999). These studies highlight the congruence between parent-child and child-sibling relationships. Based on social learning theory and on prior empirical work, we hypothesized that higher levels of parental warmth and involvement would be associated with lower levels of sibling relational aggression.

Our consideration of indirect parental influences was further informed by a nonshared family perspective (Dunn & Plomin, 1990), which directs attention to the differential parenting of siblings. A number of studies have shown that PDT, such as when parents are perceived as spending more time with or being more affectionate toward one child relative to another, is related to the quality of the sibling relationship. At the most general level, differential treatment, or favoritism, is linked to more negativity in sibling relationships (e.g., Brody, Stoneman, & Burke, 1987), particularly when PDT is perceived as unfair or without good reason (Kowal & Kramer, 1997; McHale, Updegraff, Jackson- Newsom, Tucker, & Crouter, 2000). Some evidence further suggests that adolescents are more reactive to differential treatment than are younger children (McHale, Updegraff, Jackson-Newsom, et al.). Building on the nonshared family perspective, we anticipated that when adolescents experienced more




favorable treatment (relative to their siblings), they would be less likely to initiate relational aggression.

Direct Parental Influences

Parents' direct efforts to guide or intervene in their children's sibling relationships also may be related to the frequency of relational aggression experienced by siblings. Research with young children and adolescents demonstrates links between parents' strategies for handling sibling conflict and the qualities of the sibling relationship (e.g., Kramer, Perozynski, & Chung, 1999; McHale et al., 2000). In young children's sibling relationships, parents' lack of intervention in sibling conflicts is associated with future conflict (Kramer et al.); however, there is some evidence that in older child (Kramer et al., 1999) and adolescent dyads (McHale et al., 2000), parental intervention is associated with less positive or more negative sibling relationships. This pattern of findings suggests that implications of parental intervention may differ across developmental periods. Further evidence that parents can play a role comes from intervention research. Adams and Kelley (1992), for example, demonstrated that maternal training in discipline techniques was related to a reduction in sibling aggression in early childhood sibling pairs. Thus, we explored the associations between parents' direct involvement in sibling conflicts and sibling relational aggression. We hypothesized that intervention in sibling conflict would be positively associated and parental coaching negatively associated with relational aggression. Overall, we anticipated that parental influences would be more closely linked to girls' experiences of sibling relational aggression given the greater developmental emphasis placed on girls' social relationships (Ruble & Martin, 1998) and the greater concern parents express over relational aggression in girls (Underwood, 2003).

Summary and Hypotheses

In sum, our first goal was to examine the links between sibling relational aggression and the qualities of girls' and boys' sibling relationships (i.e., intimacy, negativity, and involvement). We conceptualized relational aggression as the independent variable and hypothesized that relational aggression would occur in the context of less intimacy and involvement and

more negativity. Our second goal focused on the role of parents' indirect and direct involvement in the sib-

ling relationship and relational aggression, including parent-adolescent dyadic relationship qualities, PDT, and parents' strategies for handling sibling conflicts. For this second goal, relational aggression was the dependent variable. We hypothesized that parents' warmth and involvement and their efforts to coach their offspring would be negatively related, and differential parenting and direct intervention in sibling conflicts would be positively related, to relational

aggression. We tested our models separately for mothers' and fathers' parenting activities and examined the role of adolescents' gender in parenting dynamics, given evidence of the importance of gen- dered socialization processes during adolescence (e.g., Crouter, Manke, & McHale, 1995).

Method

Participants

Data were collected from older (i.e., firstborn) and younger (i.e., second born) siblings and both mothers and fathers in 197 families as part of a short-term lon-

gitudinal study of family relationships and adolescent development (Crouter, Bumpus, Head, & McHale, 2001; McHale, Updegraff, Tucker, & Crouter, 2000). The families were recruited via letters sent home to families of students in seven counties (13 school districts) in a northeastern state. Letters described the study and requested that parents return postcards to express their interest in the project. Eli-

gible families included nondivorced couples with a firstborn in the 8th through 10th grade and a second-born child approximately 1 to 3 years younger. The participation rate was 95% for eligible families who expressed an interest in the project. Nine families were excluded from the present analyses because, despite the initial screening procedures, they failed to meet one or more of the criteria, and three additional families were excluded because of missing data. The final sample consisted of 185 families with 99 older brothers and 89 older sisters and equal numbers of younger sisters and brothers (ns = 94).

Families were from predominantly middle- and

working-class backgrounds and resided in rural areas, towns, and small cities. Reflecting the demo-

graphics of the region (U.S. Census Bureau, 1990),



Sibling Relational Aggression • Updegraff et al. 377

participants were predominantly of European Amer- ican origin and the remaining 3% were Asian. The average annual income for families was $61,849 (SD = $34,737). Both parents had completed an average of 2 years of education beyond high school. Mean ages were 15.95 years (SD = .72) for older siblings and 13.47 years (SD - 1.02) for younger siblings. Parents had been married an average of 19.50 years (SD = 3.29).

Procedure

Data collection involved home visits and a series of nightly telephone interviews during three annual visits. Separate home interviews lasting approximately 2-3 hr were conducted with all four family members. Home interview measures for the present study included older and younger siblings' ratings of sibling and parent-adolescent relationship experiences and parents' ratings of their strategies for managing sibling conflict.

In the 2-3 weeks following the home visit, daily time-use data were collected from siblings during a series of seven nightly phone calls (five weekdays, two weekend days). Each parent participated in four of the seven calls. Specifically, these calls were designed to gather information about siblings' daily home and personal activities (i.e., excluding school activities). Using a cued-recall strategy (McHale, Crouter, & Bartko, 1992), each sibling reported on his or her involvement in 63 daily activities, including how long each event lasted (in minutes) and who else participated. From these data, we calcu- lated siblings' time spent in activities together and each sibling's time spent with their mothers and with their fathers.

Measures

Measures for the present analyses were drawn from the second year of the study when siblings' reports of relational aggression were collected.

Sibling relational aggression. Older and younger siblings completed a six-item scale to assess adolescents' perceptions of how frequently they were the

targets of relationally aggressive behaviors from their

sibling (O'Brien, 1999; O'Brien & Crick, 1995). Qualitative data were collected from school-aged sib-

lings to develop the items for this measure, and pilot work was conducted to select the final items (K. M. O'Brien, personal communication, April 18, 1999).

Sample items were "(Sibling's name) leaves me out of things when he/she is mad at me" and "(Sibling's name) tells me that he/she won't like me anymore unless I do what he/she says." Items were rated on a 5 -point Likert scale (never to very often) to indicate the frequency with which these events occurred, and summed. Cronbach's alphas were .83 for older siblings and .76 for younger siblings.

Sibling relationship qualities. Older and younger siblings described the degree of intimacy they felt with their sibling on an eight-item scale (Blyth & Foster-Clark, 1987). Higher numbers on this summed 5-point scale score indicated greater perceived intimacy. Cronbach's alphas were .86 for older siblings and .84 for younger siblings.

Siblings also rated the degree of negativity on a five-item scale designed to tap the extent to which siblings disagreed, initiated conflicts, or felt angry at each other (Stocker & McHale, 1992). Items were rated on a 5-point scale and summed to create the scale score, with high numbers indicating more negativity. Alphas were .74 and .81 for older and younger siblings, respectively.

Siblings' temporal involvement or time spent in shared activities was measured by the number of minutes siblings participated in activities together, using daily activity data. The number of minutes siblings spent in activities together was aggregated across the seven calls to measure siblings' temporal involvement.

Parent-adolescent relationship qualities. Siblings described the degree of warmth in their relationship with mothers and fathers using the 24-item Child Report of Parental Behavior Inventory (Schwarz, Barton-Henry, & Pruzinsky, 1985). Higher scores on this summed scale reflect greater warmth in the relationship. Alphas were above .91 for both siblings' descriptions of mother- and father-adolescent warmth.

Mothers' and fathers' temporal involvement with each sibling was assessed by time-use data collected during the series of nightly phone interviews. Specif- ically, the duration (in minutes) that each sibling reported spending in dyadic activities with their mothers was aggregated across the seven phone calls; a parallel measure was created for fathers' involvement with each sibling. We used siblings' reports because they participated in all seven calls, whereas parents only participated in four phone calls. Corre- lations between parents' and siblings' reports of temporal involvement for the four phone calls in which




they both participated ranged from r = .56, p < .001 to r= .69, p< .001.

Older and younger siblings also rated the degree of differential treatment they perceived with respect to parental warmth (i.e., "Who does your mother/ father seem more affectionate or nice to?") and temporal involvement (i.e., "Who does your mother/ father spend more time with?") using the format of the Sibling Inventory of Differential Experiences (Daniels & Plomin, 1985). Siblings responded to these items on a 5-point rating scale that was recoded into three groups: (1) older siblings favored, (2) equal treatment, and (3) younger siblings favored.

Parents' direct involvement in the sibling relationship. Mothers and fathers completed a measure of parents' strategies for handling sibling conflict that included three subscales (see McHale, Updegraff, Tucker, et al., 2000). For a series of five vignettes about problems that may have occurred between the siblings during the past year, parents rated the extent to which they used particular strategies for handling the conflict. In the present analyses, we included mothers' and fathers' coaching (e.g., giving advice about how to handle the conflict) and intervention (e.g., punishing the siblings). Cronbach's alphas were above .85 for mothers' and fathers' reports for both subscales.

Results

Preliminary Analyses

As a preliminary step, we conducted a factor analysis of the three measures of sibling relationship quality rated by adolescents (i.e., intimacy, negativity, and relational aggression) to ensure that relational aggression was a distinct relationship dimension. Principal components analyses, conducted separately for older and younger siblings' ratings, revealed three factors based on examination of the scree plots and eigenvalues. For older and younger siblings, intimacy represented the first factor (eigenvalues = 5.45 and 5.64, respectively), relational aggression items comprised the second factor (eigenvalues = 2.85 and 3.32, respectively), and negativity items represented the third factor (eigenvalues = 1.66 and 1.62, respectively).

Next, we conducted a series of 2 (older sibling's sex) x 2 (younger sibling's sex) x 2 (sibling) mixed model analyses of variance (ANOVAs) to test for sex

constellation differences in relational aggression and other qualities of the sibling relationship (i.e., inti-

macy, negativity, and temporal involvement). Means and standard deviations are shown in Table 1. We found no evidence of sex or dyad constellation effects for relational aggression. However, consistent with previous work (e.g., Buhrmester, 1992), we found an Older Sibling's Sex x Younger Sibling's Sex interaction for sibling intimacy, F(l, 181) = 1 1.48, p < .01, and Tukey's follow-up tests showed that sister-sister pairs reported higher levels of inti-

macy compared to all other dyads. An overall sibling effect, F(l, 181) - 8.13, p < .01, was qualified by a Sibling X Younger Sibling's Sex interaction, F(l, 181) = 4.71, p < .05; younger sisters but not

younger brothers reported higher levels of intimacy than their older siblings. No differences emerged for

sibling conflict. For involvement, there was an Older

Sibling's Sex x Younger Sibling's Sex interaction, ^(1, 179) = 9.84, p < .01. Follow-up tests showed that sister-sister pairs spent more time together than mixed-sex pairs.

Goal 7 : Links Between Sibling Relational Aggression and Qualities of the Sibling Relationship

To address our first goal, we tested a series of multi- level models using the Hierarchical Linear Modeling program (HLM; Raudenbush & Bryk, 2001). This

approach is advantageous because it extends multiple regression to incorporate nested data. In the present study, because there were two siblings from each

family, siblings were nested within the family. We also included sex, birth order, and sex composition of the sibling dyad to test whether differences

emerged for any of these individual or dyad characteristics. The two-level model partitions variance into (a) between-sibling (or within-family) and (b) between-family components. At Level 1, the

between-sibling model, explanatory variables that were specific to each sibling (i.e., each sibling's reports of relational aggression, sex, birth order) were included. Additionally, interaction terms between all the Level 1 variables were computed and included. Continuous variables were centered prior to creating interaction terms, and dichotomous variables were effect coded (.5 vs. -.5). At Level 2, the between-

family model, the sex composition of the sibling dyad (same vs. mixed sex) was included. Cross-level interactions with sex composition of the sibling dyad and the Level 1 predictors also were computed to




Table 1. Means and Standard Deviations for Relational Aggression, Intimacy, Negativity, and Temporal Involvement

Sibling Dyad Sex Constellation

Older Older Older Older Sister-Younger Sister-Younger Brother-Younger Brother-Younger

Sister Brother Sister Brother

M SD M SD M SD M SD

Relational aggression Older siblings' report 13.53 4.38 13.69 4.96 13.13 3.70 13.35 4.02 Younger siblings' 14.00 4.74 13.12 4.31 13.94 5.34 13.76 3.62 report

Intimacy Older siblings' report 24.42 6.15 21.57 5.78 21.40 5.31 22.80 5.04 Younger siblings' report 27.18 5.62 21.88 6.56 22.83 5.79 23.06 5.01

Negativity Older siblings' report 26.62 5.83 26.24 4.95 26.81 5.48 27.20 4.29 Younger siblings' report 26.80 4.75 24.93 5.38 25.98 6.90 27.98 5.10

Temporal involvement* Older siblings' report 8.64 6.26 6.26 4.79 6.14 4.13 8.19 6.42 Younger siblings' report 9.32 6.00 5.93 4.39 6.38 4.50 8.37 6.22

aMeasured as hours per seven phone calls.

examine all possible two-, three-, and four-way interactions. Analyses were conducted separately by sibling relationship dimension. The equations for the

complete model are presented in the Appendix. In

describing the results, we focus only on main effects and interactions involving relational aggression.

Sibling intimacy. The analysis revealed a significant main effect of relational aggression. As hypothesized, relational aggression was negatively associated with sib-

ling intimacy, y = -.35, SE= .06, p < .001, such that

greater relational aggression predicted less intimacy between siblings. There were no interactions, suggest- ing that the overall negative association between

sibling intimacy and relational aggression was consistent for older and younger siblings, boys and girls, and siblings from the four dyad sex constellations.

Sibling negativity. As with sibling intimacy, the HLM model revealed a significant main effect of relational aggression at Level 1, y - .72, SE = .05, p < .001; higher scores on relational aggression were linked to greater sibling negativity. At Level 2, a significant main effect of sex composition of the sibling dyad, y = .92, SE = A6, p < .05, was qualified by a significant Relational Aggression x Sex x Birth Order x Sex Composition interaction, y = 1.06, SE = .42, p < .05, but follow-up analyses were not

significant.

Siblings' temporal involvement. The third HLM model examined siblings' temporal involvement and revealed no significant effects involving relational

aggression.

Goal 2: Exploring Links Between Parenting Dynamics and Sibling Relational Aggression

Our second goal was to investigate the connections between parenting dynamics and sibling relational

aggression. Specifically, we tested associations between three dimensions of parenting (i.e., parent- adolescent warmth and involvement, PDT, and

parents' direct involvement in the sibling relation-

ship) and sibling relational aggression. Parent-adolescent warmth and involvement. We

tested HLM models to examine parent-adolescent warmth and temporal involvement as predictors of

sibling relational aggression. These analyses were conducted separately for mothers and fathers and by predictor (i.e., separately for warmth and temporal involvement). Similarly to the previous models, variance was partitioned into two levels: (a) between-

sibling and (b) between-family components (see the

Appendix). With respect to the connection between parent-

child warmth and sibling relational aggression, the




HLM models revealed similar effects for mothers and fathers. Greater parental warmth predicted less relational aggression between siblings, y = - 1.35, SE = .35, p < .001 for mothers, and y = -1.21, SE = .31, p < .001 for fathers. Neither model revealed significant interactions involving structural characteristics of the dyad.

For the model examining the connection between maternal temporal involvement and sibling relational aggression, no effects or interactions were significant. However, there was a significant main effect for paternal involvement, y = -5.16, SE - 2.43, p < .05: When youth spent more time in the company of their fathers, they exhibited lower levels of relational aggression toward their siblings.

Parental differential treatment. We conducted a series of 2 (sibling gender) x 3 (differential treatment, younger more; equal treatment, older more) x 2 (sibling: older vs. younger) mixed model ANOVAs, with siblings' reports of relational aggression as the dependent variable. This analytic strategy was selected because all the predictors were categorical variables and mixed model ANOVAs take into account the correlated nature of data from siblings. This approach is more parsimonious and comprehensible for categorical data than HLM and is consistent with recommendations for analyzing this type of data (Hertzog & Rovine, 1985; Rovine & von Eye, 1991).

The mixed model ANOVAs including older siblings' sex and perceptions of mothers' and fathers' differential warmth were not significant. In contrast, the 2 (younger sibling's sex) x 3 (differential treatment) X (Sibling) mixed model ANOVAs including younger siblings' reports of differential treatment as the independent variable and both siblings' reports of relational aggression as the dependent variable were significant. For younger siblings' reports of mothers' differential warmth, we found an overall differential treatment effect, E(2, 179) = 5.08, p < .01, and follow-up tests revealed that siblings' average reports of relational aggression were lower when younger siblings perceived equal treatment (M =

13.04) as compared to when younger siblings were favored (M = 14.96). For fathers' differential warmth, we also found an overall differential treatment effect, F(2, 179) = 6.75, p < .01, which was qualified by an interaction with younger siblings' sex, F(2, 179) = 4.41, p < .05. Follow-up tests showed that, for dyads that included younger sisters, the frequency of relational aggression for the dyad as

a whole was highest when younger sisters were favored by fathers (M = 16.16) as compared to

equal treatment (M = 12.50) or older siblings being favored (Af= 13.04).

Older siblings' reports of maternal and paternal differential time and younger siblings' reports of maternal differential time were not related to sibling relational aggression. However, for younger siblings' reports of differential time with fathers, there was an overall differential treatment effect, revealing that

siblings reported the least relational aggression when

younger siblings perceived that older siblings were favored (M= 12.69) as compared to when they perceived equal treatment (M = 13.26) or the younger sibling being favored (M = 14.58), F(2, 179) =

5.17,/ <• 01. Parents' direct involvement in the sibling relation-

ship. We conducted a series of HLM models with older and younger siblings' reports of relational

aggression as the outcome variable and parents' strategies for handling sibling conflicts as the predictors. Analyses were conducted separately for mothers and fathers and for each strategy (i.e., parents' use of

coaching and intervention). Again, variance was partitioned into two levels: (a) between-sibling (within- family) and (b) between-family components (see the

Appendix). At Level 1, the between-sibling model, the sex of each child, birth order, and the Sex X Birth Order interaction were entered. Because parents' strategies were shared by siblings, the measures of parents' coaching and intervention were included at Level 2 (the between-family model). Finally, interactions were computed to examine all possible two-, three-, and four-way interactions (see the

Appendix). The model predicting siblings' relational aggres-

sion from maternal coaching revealed a Coaching x Sex Composition x Sex interaction, y = -.39, SE = .19, p < .05, but follow-ups were not significant, and there were no significant effects for parental coaching.

For the model predicting siblings' relational

aggression from mothers' intervention, there was a significant main effect of maternal intervention, y =

.08, SE - .03, p < .01, showing that, when mothers intervened in sibling conflict, sibling relational

aggression was more frequent for both siblings. However, the main effect was qualified by a significant Maternal Intervention X Sex interaction, y = - .21, SE - .05, p < .001. Maternal intervention was associated with higher levels of relational




aggression for daughters (M - 15.92 for high maternal intervention vs. M = 12.37 for low maternal intervention) but not for sons {M - 13.72 and M - 14.14 for high vs. low maternal intervention).

For the model predicting siblings' relational aggression from fathers' intervention, there were two significant two-way interactions. A Paternal In- tervention x Sex interaction, y = - .19, SE - .06, p < .01, suggested that fathers' intervention was more strongly linked to girls' than to boys' relational aggression (Ms = 15.27 and 13.12 for high vs. low paternal intervention with daughters and Ms - 13.40 and 14.34 for high vs. low paternal intervention with sons). A Paternal Intervention x Sex Composition of the sibling dyad interaction, y = - .13, SE - .07, p - .05, suggested further that paternal intervention was more strongly linked to relational aggression in same-sex as compared to mixed-sex dyads {Ms - 14.85 and 13.21 for high vs. low paternal intervention with same-sex dyads and Ms - 13.82 and 14.25 for high vs. low paternal intervention with mixed-sex dyads).

Discussion

This study was designed to investigate the links between siblings' experiences of relational aggression and other qualities of the sibling relationship as well as broader parenting dynamics in families with adolescents. We adopted a multi-informant and multi- method approach that included self-report data from older and younger siblings and their parents and daily activity data from adolescent siblings. Although relational aggression has received attention in the context of peer group interactions (Cairns et al., 1989; Crick et al., 2001), little is known about this potentially important dynamic in the context of

sibling relationships. Our findings revealed that relational aggression is tied to qualities of both sibling and parent-adolescent relationships. However, in

considering these findings, it is important to note the limitations of this work. First, this study was correlational in design, preventing us from drawing conclusions about direction of effects. An important next step will be to conduct longitudinal studies and

experimental interventions to further explore the direction of effects linking sibling relational aggression and family relationship qualities. Second, families were predominantly European American, and

there is a need for future work with ethnically diverse samples. Relationally aggressive behaviors between siblings may be differentially linked to family dynamics in other cultural contexts. In addition, it will be important to explore these sibling relationship dynamics in other family structures (e.g., single-parent, divorced, and remarried families). Finally, it will be important to conduct additional research to further explore the measurement of relational aggression in the context of sibling relationships. This study represents a first step in exploring relational aggression in the context of adolescents' sibling relationships and broader family dynamics.

Sibling Relational Aggression and Other Qualities of the Sibling Relationship

Our results revealed that relational aggression is a distinct dimension of the sibling relationship; as in the case of peer relationships, it differs from overt hostil- ity between siblings. We also found that relational aggression was linked to sibling intimacy and negativity in expected ways. Specifically, relational aggression occurred within the context of less emotional support and more negativity between siblings, a pattern that is consistent with perspectives on social development (Sullivan, 1953). Although we anticipated that relational aggression might be particularly harmful for girls' as compared to boys' relationships with siblings, our findings suggest that relational aggression in the context of the sibling relationship may hinder closeness and support for both girls and boys in adolescence. We also considered the possibility that connections between relational aggression and sibling quality may be stronger for girls with sisters as compared to other dyads. However, our findings suggested that relational aggression was associated with low levels of intimacy and high levels of negativity for all siblings, regardless of the sex constellation of the sibling dyad. Given that adolescence is a developmental period when peer relationships become more salient (Sullivan, 1953), efforts to harm social relationships may be equally salient for all youth at this stage of development.

Contrary to our expectations, we did not find that sibling relational aggression was associated with the amount of time siblings spent in shared activities. The pattern of findings in this study and in other work suggests that adolescents spend signifi- cantly more time with same-sex than with opposite- sex siblings (Buhrmester, 1992). It may be that




common interests are more important than behaviors such as relational aggression in predicting the time that siblings spend together in adolescence.

Overall, our findings highlight associations between the emotional climate of the sibling relationship (i.e., intimacy and negativity) and relational aggression. However, it is important to note that relational aggression may precede or be the result of problematic sibling relationships. Given the general pattern of findings, intervention efforts aimed at reducing sibling relational aggression may have implications for sibling relationship quality in the same way that interventions have been successful in reducing physical aggression between siblings (e.g., Adams & Kelley, 1992).

We anticipated that relational aggression would be more strongly associated with qualities of the sibling relationship for younger than for older siblings. Our findings suggested more similarities than differences in the links between relational aggression and sibling relationship quality for older and younger siblings. Adolescence is a developmental period when sibling relationships are thought to become more egalitarian and more similar to peer relationships in their balance of power than in earlier developmental periods (e.g., Buhrmester, 1992). This transition to a more egalitarian relationship may mean that the greater significance of the relationship for younger siblings is less common than in earlier developmental periods. It will be important to extend studies of sibling relational aggression to other developmental periods to learn about the nature of relational aggression for both siblings in the dyad from early childhood through adolescence.

Sibling Relational Aggression and Parenting Dynamics

We examined the role of both indirect and direct parenting processes in sibling relational aggression. Our findings revealed consistent connections between parent- adolescent relationship qualities (i.e., warmth, involvement) and older and younger siblings' experiences of relational aggression. When older and younger siblings reported lower levels of acceptance from both mothers and fathers, they experienced more relational aggression. In addition, when fathers (but not mothers) spent less time with siblings, relational aggression was more frequent. One interpretation of these findings, consistent with a social learning perspective and Parke and Bund's (1998) model of parenting, is that less positive

relationship experiences with mothers and fathers contribute to sibling relational aggression. The other

possibility is that parents are less warm toward and involved with siblings who engage in high levels of relational aggression. Findings that fathers' but not mothers' temporal involvement was linked to sibling relational aggression were consistent with some prior work on other sibling relationship dimensions in doc-

umenting stronger connections between the father- child relationship (as compared to the mother-child

relationship) and sibling relationship qualities (Stocker & McHale, 1992). As we suggested, mothers' parental role may be more scripted, and the greater variability among fathers may make for stronger linkages (Crouter et al., 1999). In particular, fathers spend a greater per- centage of their time in leisure and play-oriented activities with their offspring (Parke & Buriel, 1998). This

may mean that the father-child relationship is a more relevant model for sibling relationships than the mother-child relationship, which tends to involve more

caregiving. Grounding our study in Parke and Buriel's

(1998) model of parenting, we also examined parents' strategies for handling sibling conflict as potential correlates of relational aggression. Our findings revealed that parents' intervention in sibling conflicts (particularly girls' sibling conflicts), but not their efforts to coach siblings on conflict resolution, were associated with sibling relational aggression. In this study, parents' direct intervention encompassed more authoritarian strategies (e.g., punishing sib-

lings) and thus, it may not be surprising that parental intervention was linked to more relational

aggression. However, the fact that coaching was not an effective strategy for reducing relational aggression was surprising, given findings on the efficacy of such an approach in early childhood (Kramer et al., 1999). It may be that parents intervene in the early years to help siblings learn how to resolve conflicts, but in later years, parental intervention is primarily in response to problematic relationship dynamics. Another possibility is that when parents are involved in girls' sibling conflicts, girls respond by using relational aggression with their siblings. To the extent that girls are dissatisfied with how their parents step in and administer punishments, they may retaliate

against their siblings by using relational aggression. Although it is not possible to determine the direction of effects from this study, our findings imply that intervention programs should highlight the negative implications of power-assertive or authoritarian




approaches and provide information to parents on the potentially positive implications of their spending time in the company of the sibling dyad (McHale, Updegraff, Tucker, et al., 2000).

PDT was associated with siblings' experiences of relational aggression. The overall pattern showed that dyads reported the lowest levels of relational aggression when younger siblings perceived mothers and fathers as treating siblings equally. This pattern is consistent with work on differential treatment and sibling relationship dynamics in revealing more positive and less

negative relationships between siblings who perceive equal or fair treatment (e.g., Kowal & Kramer, 1997; McHale, Updegraff, Jackson-Newsom, et al., 2000). Relational aggression toward younger girls was pro- nounced when fathers were perceived as being warmer toward these girls as compared to their older siblings. Because fathers' favoritism of younger daughters may be nonnormative (McHale & Crouter, 1996), this may be a dynamic to which siblings are particularly reactive. We did not find connections between older siblings' perceptions of differential treatment and relational aggression. Older siblings, who, in this sample, were in middle to late adolescence, may be more focused on their experiences outside the family (e.g., peer and romantic relationships) and less focused on PDT.

Implications

Relationally aggressive behaviors in the peer context, particularly among young adolescent girls, have received considerable attention in the media and have been highlighted as a potential concern among parents (Underwood, 2003). Our findings suggest the

importance of attending to relational aggression within the sibling relationship as well. Intervention

programs designed to address sibling relational

aggression and the role that parents may play in promoting or discouraging this harmful element of the

sibling relationship have the potential to provide important information as well as contribute to theory about sibling relationships in adolescence.

Experimental interventions designed to target elements of the sibling relationship are relatively sparse and have tended to focus on reducing sibling aggression and conflict in young children's and preadolescents' relationships (for a review, see Kramer, 2004). Kramer (2004) proposes that a limitation of sibling intervention programs is a focus on decreasing negative behaviors (e.g., conflict or aggression) without a complementary component on fostering prosocial

interactions (e.g., initiation of play, perspective tak- ing). With young children, this may translate to teaching social skills for initiating and declining play activities, expressing feelings, and resolving conflicts. In adolescence, our findings suggest that teaching adolescents skills that promote emotional support may foster more positive interactions and reduce relational aggression. In addition, research suggests that the family's shared leisure events - the extent that siblings and parents engage in activities together - are linked to positive sibling relationship qualities (McHale, Updegraff, Tucker, et al., 2000). Thus, intervention efforts designed for the reduction of sibling relational aggression may be most effective if combined with program elements that foster in- creased involvement of adolescent sisters and brothers in activities that both enjoy, and in turn, emotional support and closeness in the sibling dyad.

The connections between sibling relational aggression and parenting dynamics found in this study direct attention to the importance of including a parent component in addition to a sibling component in efforts to intervene. Parent training has been successful in previous intervention work to improve sibling relations (e.g., Adams & Kelley, 1992). Parents may benefit from knowledge about the nature of relational aggression, its connections to sibling dynamics, and the ways in which parent-adolescent relationship quality, strategies for handling sibling conflicts, and differential treatment are related to relational aggression. If parents are taught specific skills for handling sibling relational aggression and for promoting positive sibling involvement, a parent component may further increase the efficacy of intervention programs.

Moving beyond program-level recommendations, our findings also provide direction for profes- sionals working with families. Parents and children indicate that conflict over how siblings get along is a primary source of parent-child conflict in both middle childhood and early adolescence (McHale & Crouter, 2003). These findings highlight that relational aggression, in addition to overt conflict, may contribute to siblings' problematic interactions. Working with parents and siblings to identify relationally aggressive and overt conflict patterns, pro- viding alternative strategies for handling anger, and developing approaches for enhancing positive fea- tures of the relationship may enable siblings to develop more harmonious relationships.

It is also important to consider the family dynamics that may promote or discourage sibling relational




aggression in working with individual families. Our findings draw attention to the role of parenting dynamics - adolescents' individual relationships with their mothers and fathers, the ways in which both mothers and fathers manage daughters' sibling conflicts, and the degree of preferential treatment that younger siblings perceive from parents - as important. Talking with adolescent siblings and parents about adolescent siblings' perceptions of preferential treatment and fairness (Kowal & Kramer, 1997; McHale, Updegraff, Jackson-Newsom, et al., 2000), for example, may aid in identifying family dynamics to which siblings react with relational aggression. To the extent that clinicians are able to explore the potential contributions of these different parenting processes in their work with individual families, efforts to alter family dynamics that promote or discourage relational aggression may be more successful. Such efforts can have larger effects on the family system, given links between sibling conflict and parental stress (e.g., Patterson, 1986).

Our findings also provide some insights for pro- fessionals working with parents of girls. Although girls and boys were equally likely to experience relational aggression from their siblings, links between some elements of parenting and relational aggression were specific to families with girls. When parents intervened in girls' sibling conflicts, higher levels of relational aggression were apparent between siblings. Parents' efforts to coach adolescents in resolving sibling conflict, in contrast, were not associated with relational aggression for girls. These findings highlight the importance of attending to the ways parents handle sibling conflicts with daughters when relational aggression is a problem in the family. Also notable was the role of preferential treatment, with relational aggression being more prominent when younger girls received more favorable treatment from fathers than their older siblings. Because it is uncommon for younger girls to receive preferential treatment from fathers (McHale & Crouter, 1996), siblings may respond negatively to this family dynamic. Helping parents address these issues in the context of everyday family life may prove beneficial.

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Appendix.

Equations for Sibling Relationship and Indirect Parenting Models (Sibling Relationship Example)

Level 1: Y- (30 + Pi (relational aggression) + P2 (gender) + P3 (birth order) + p4 (Gender x Birth Order) + P5 (Relational Aggression x Gender) + P<$ (Relational Aggression x Birth Order) + (37 (Relational Aggression x Gender x Birth Order) + r

Level 2: Po - Too + Yoi (sex composition of the sibling dyad) + u0 Pi - Yio + Yn (sex composition of the sibling dyad) P2 - Y20 + Y21 (sex composition of the sibling dyad) P3 = Y30 + Y31 (sex composition of the sibling dyad) p4 = Y40 + Y4i (sex composition of the sibling dyad) P5 = Y50 + Y51 (sex composition of the sibling dyad) P<5 = Y6o + Y6i (sex composition of the sibling dyad)

Equations for Direct Parent Influence Models (Mother Coaching Example)

Level 1: Y= % + Pi (gender) + P2 (birth order) + p3 (Gender x Birth Order) + r Level 2: Po = Yoo + Yoi (sex composition of the sibling dyad) + yO2 (maternal coaching) +

Y03 (Maternal Coaching x Sex Composition of the Sibling Dyad) + u0 Pi = Yio + Y11 (sex composition of the sibling dyad) + Y12 (maternal coaching) +

y13 (Maternal Coaching x Sex Composition of the Sibling Dyad) P2 - Y20 + Y21 (sex composition of the sibling dyad) + y22 (maternal coaching) +

Y23 (Maternal Coaching x Sex Composition of the Sibling Dyad) P3 - Y30 + Y31 (sex composition of the sibling dyad) + 732 (maternal coaching) +

733 (Maternal Coaching x Sex Composition of the Sibling Dyad)



relational aggression in adolescents' sibling relationships: links to sibling and...

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