Child Development, November/December 2000, Volume 71, Number 6, Pages 1597–1610 Adolescents’ Sex-Typed Friendship Experiences: Does Having a Sister versus a Brother Matter? Kimberly A. Updegraff, Susan M. McHale, and Ann C. Crouter This study examines the connections between having a sister versus a brother and coming from a same-sex versus an opposite-sex sibling dyad and the degree of sex-typing in adolescents’ friendship experiences, in- cluding the qualities of their friendships (i.e., intimacy, control) and their friends’ personal attributes (i.e., se typed leisure interests, expressive and instrumental personality qualities). Participants were 159 firstb secondborn adolescent sibling pairs ( M 5 14.94 years and M 5 12.43 years, respectively) and a close friend of each sibling ( N 5 636, including siblings and friends). Data were collected during home visits with siblings and telephone interviews with friends of siblings. The results suggested that sisters may learn control tactics from their brothers that they apply in their friendships; boys, however, were less likely to model the emotiona intimacy that characterized their sisters’ experiences with friends. In addition, coming from an opposite-sex sibling dyad was linked to sex-typing in friends’ personal attributes, particularly their masculine leisure inter ests and instrumental personality qualities. Sisters and brothers may provide unique opportunities to learn about sex-typed relationship experiences in early adolescence, a time when gender segregation in the peer co text is pervasive. INTRODUCTION Having a sister versus a brother has been linked to sex-typing in children’s and adolescents’ personal characteristics, interests, and behaviors (Bigner, 1972; Brim, 1958; Grotevant, 1978; Ickes & Turner, 1983; Koch, 1960;Leventhal,1970;Sutton-Smith, 1982). Most of this work has focused on the potential influ- ences of siblings’ sex on young children’s sex-typed personality qualities (Brim, 1958; Koch, 1960; Sutton- Smith, 1982). A possibility that has received little at- tention is that the presence of a same- versus oppo- site-sex sibling may be associated with sex-typing in the nature of girls’ and boys’ experiences in interper- sonal relationships, particularly those with peers. In- teractions with friends provide an important context for the expression of sex-typed preferences during early adolescence, a developmental period when youth spend considerable time in gender-segregated activities with age mates (Carter, 1987; Hartup, 1983; Maccoby, 1998), and when there are dramatic differ- ences in the nature of girls’ versus boys’ friendships and peer interactions (Berndt, 1982; Buhrmester & Furman, 1987; Maccoby, 1998). This study addressed the question of whether ado- lescents’ sex-typed experiences with friends differ as a function of their siblings’ sex and the sex constella- tion of the sibling dyad (i.e., same-sex versus mixed- sex pair). We focused on two developmentally signif- icant aspects of young adolescents’ peer experiences: the qualities of their friendships and the personal characteristics of their close friends (Hartup, 1993). Our first goal was to determine whether having a sis- ter versus a brother and/or coming from a same-sex versus an opposite-sex sibling dyad was linked to the extent of sex-typing in adolescents’ behavior toward their friends; emotional intimacy and direct contro were the foci of these analyses. Emotional intimacy and self-disclosure are defining characteristics of girls’ friendships in early adolescence (e.g., Blyth & Foster-Clark, 1987;Buhrmester & Furman, 1987), whereas boys’ relationships with friends are often based on involvement in shared interests and activitie (Berndt, 1982; Berndt & Perry, 1990; Savin-Williams Berndt, 1990). The control and influence strategie girls and boys use in their peer interactions are also notably different, with girls tending to rely on indirec or passive approaches and boys on directives and com mands (Crick, 1996; Maccoby, 1990; Thorne, 1986). Two competing hypotheses have been offered to explain the links between siblings’ sex, the sex con- stellation of the sibling dyad, and girls’ and boys’ sex- typed personal qualities, interests, and behaviors. First, in accordance with social learning theory (Mis- chel, 1966), a series of studies has shown that later- borns model their behavior after their older siblings, assuming sex-typed qualities similar to those of their sisters or brothers (Bigner, 1972; Brim, 1958; Gr field & Weatherley, 1986; Koch, 1960; Rosenberg Sutton-Smith, 1964, 1968; Sutton-Smith & Rosenberg © 2000 by the Society for Research in Child Development, Inc. All rights reserved. 0009-3920/2000/7106-0011