Issues of equality and fairness and invasion of the personal domain, 2 previously identified topic areas of adolescent sibling conflict (N. Campione-Barr & J. G. Smetana, 2010), were examined in 145 dyads (Mfirst-born = 14.97, SD = 1.69 years; Msecond-born = 12.20, SD = 1.90 years) for their differential effects on youths' emotional adjustment over 1 year. The impact of internalizing symptoms on later sibling conflicts also was tested. Invasion of the personal domain conflicts were associated with higher levels of anxiety and lower self-esteem 1 year later, whereas Equality and Fairness issues were associated with greater depressed mood. Conversely, greater internalizing symptomatology and lower self-esteem predicted more of both types of conflict. Moderating influences of gender and ordinal position were also examined.

Disclosure, or revealing personal information to others, is important for the development and maintenance of close relationships (Jourard, 1971; Rotenberg, 1995). More recently within developmental psychology, however, the focus has been the study of adolescent disclosure to parents as a means of information management regarding their daily activities. This research assumes that a) disclosure between multiple adolescents and parents within the same family are similar, and b) only information transmitted from adolescents to parents is important for adolescent well-being. Thus, this article presents the findings of 2 within-family studies to investigate differences in the amount and social domain (Smetana, 2006; Turiel, 2002) of youth disclosure to mothers versus siblings, and the influence of disclosure to siblings on relationship quality and youth emotional adjustment. Study 1 utilized 101 sibling dyads with youth ranging in age from 11-21 years, but all siblings living together. Study 2 investigated a sample of 58 sibling dyads in which all first-borns were first-year college students and all second-borns were in high school. All participants completed questionnaire measures to assess study variables. Findings revealed that while youth disclosed more to mothers than siblings, this difference disappears by emerging adulthood, particularly depending on the domain of the issue. Additionally, while greater disclosure among siblings was positive for the quality of the relationship, sibling disclosure was differentially associated with emotional adjustment depending on whether youth were the disclosers or being disclosed to, the domain of the issues disclosed, and the gender composition of the dyad.

Family researchers have acknowledged the importance of sibling relationships across the life span, but little is known about how this relationship functions during the transition from adolescence to emerging adulthood. The present study therefore examined how two domains of adolescent sibling conflict (equality and fairness issues and personal domain invasions) are related to sibling relationship quality after firstborns leave home to attend college, from the perspectives of firstborn and secondborn siblings from the same families. Our findings suggest that frequent or intense sibling conflicts during adolescence may be related to more positive and less negative sibling relationships the first year after older siblings leave home, and that conflicts surrounding issues of equality and fairness may facilitate more egalitarian relationships during emerging adulthood for some siblings. It therefore seems that the sibling relationship during the adolescent years may have important implications for its long-term functioning into adulthood.

The sibling relationship has been deemed the quintessential "love-hate relationship." Sibling relationships have also been found to have both positive and negative impacts on the adjustment of youth. Unlike previous research, however, the present study examined the associations between siblings' positive and negative body-related disclosures with relationship quality and body-esteem. Additionally, ordinal position, individual sex, and sibling sex composition were tested as moderators. Participants included 101 predominantly White and middle class adolescent sibling dyads (54 % female adolescents, with relatively equal sibling gender compositions). Older siblings were, on average, 16.46 (SD = 1.35) years old with younger siblings an average of 13.67 (SD = 1.56) years. Adolescents completed questionnaires and data were analyzed using Actor-Partner Interdependence Modeling, which focused on disclosure to and from dyad members. In general, sibling body-related disclosure was positive for the quality of the sibling relationship, regardless of the valance of disclosure. Also, adolescents' body esteem was greater when adolescents reported disclosing (i.e., actor-effects) about positive or negative body issues to their siblings (particularly for females). Conversely, when adolescents received positive or negative body-related disclosures from their siblings (i.e., partner-effects), adolescents reported lower levels of body esteem (particularly for girls and younger siblings). Thus, the impact of body-related disclosure on adolescents' feelings of body esteem appear to be associated more with whether they are the discloser or the one being disclosed to, while the impact on the quality of the relationship has simply more to do with whether or not they are generally disclosing to one another.

First-and second-born adolescents' and their parents' perceptions of adolescents' decision-making autonomy were compared from ages 12 to 19 in a longitudinal sample of 145 predominantly White, middle class families. Utilizing a multivariate, multilevel modeling approach, differences in perceptions of adolescents' autonomy between parents and each adolescent, as well as by social-cognitive domain were examined. The present study found that when comparing parents' perceptions of their children at the same age, second-borns were granted more autonomy regarding conventional issues than first-borns during early adolescence, but by later adolescence first-borns were granted more autonomy regarding prudential issues than second-borns. However, comparisons between adolescents' and siblings' perceptions showed no differences. Potential reasons for, and implications of, differences in perceptions of adolescent autonomy are discussed.