Sibling relationships play an important role in human development, promoting cognitive, social and emotional competence and contributing to overall well-being over the lifespan. To date, only a handful of empirical studies have analyzed changes in sibling relationship quality during adulthood. The present study therefore aimed to analyze the quality of sibling relationships during adulthood, examining the role of these relationships in promoting individual’s quality of life. Participants. 288 participants (124 males and 164 females) divided into two groups: 148 young adults aged 20 to 35 and 140 adults aged 40 to 55. Measures. To measure sibling relationship qualitative dimensions the Italian version (Tani, Guarnieri, Ingoglia, submitted) of the Adult Sibling Relationship Questionnaire - ASRQ (Stocker, Lanthier, Furman, 1997) was administered. To measure the quality of life the cluster Quality of life of the Psychological Treatment Inventory - PTI (Gori, Giannini, Schulberg, 2008) was administered. Results revealed that, due to the achievement of a greater maturity, adult sibling relationships were characterized by fewer negative aspects, linked to conflict and rivalry, than were young adult sibling relationships. At the same time, adult sibling relationships were characterized by higher levels of warmth than were young adult sibling relationships. Sibling relationship quality was a significant predictor of individual’s quality of life also during adulthood.
Keywords: Sibling relationship, quality of relationships, adulthood, psychological well-being.