Sibling relationships and best friendships in young adulthood: Warmth,conflict, and well‐being

Although much work addresses the importance of siblings and friendships in separate investigations, few studies simultaneously examine both relationships. Young adults (N= 102, M age = 18.7) were surveyed about their friendships, their sibling relationships, and their psychological well‐being (assessed by self‐esteem and loneliness). Participants with harmonious (high warmth, low conflict) sibling relations and same‐gender friends had the highest well‐being. Participants with affect‐intense (high warmth, high conflict) sibling relationships had low well‐being. However, participants who had low‐involved (low warmth, low conflict) and affect‐intense same‐gender friendships did not differ in well‐being. When examining joint effects, having a harmonious same‐gender friendship compensated for having a low‐involved sibling relationship, but having harmonious sibling relations did not compensate for having low‐involved friendships. Overall, the results underscore the importance of positive and negative relationship properties and the joint effects of multiple relationships.