sibling pairs (FI) in non-divorced families, and 95 full sibling pairs (FS), 60 half sibling pairs (HS), and 44 genetically unrelated sibling pairs (US) in stepfamilies who were together for at least 5 years at the time of the first assessment. Adolescents were 11 to 22 years old (M = 15.5 years; SD = 2 years). Siblings were within 4 years of age of each other (M= 1.6 years; SD = 1.3 years), and lived in the same two-parent household at least 50% of the time for at least 5 years prior to the first assessment.
