title: Peer network overlap in twin, sibling, and friend dyads.
abstract: Research suggests that sibling-peer connections are important for understanding adolescent problem behaviors. Using a novel behavioral genetic design, the current study investigated peer network overlap in 300 child-child pairs (aged 7-13 years) in 5 dyad types: monozygotic (MZ), dizygotic twins, full siblings (FSs), friend pairs, and virtual twins (i.e., same-aged, genetically unrelated siblings). Genetic relatedness, sex composition, and age differences contributed to peer overlap in sibling dyads. MZ twins showed the highest overlap (82%), opposite-sex FS pairs showed the lowest overlap (27%), and friend pairs (48%) were close to the mean (53%). Social contact variables and self-reported relationship intimacy predicted additional variance in peer overlap. The roles of genotype-environment correlational and shared environmental processes in the sibling-peer connections are discussed.
authors.affiliation: Department of Psychology, University of San Francisco, San Francisco, CA 94117, USA. mcguire@usfca.edu
authors.forename: Shirley
authors.initials: S
authors.lastname: McGuire
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Segal
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology; D000367:Age Factors; D002648:Child; D002652:Child Behavior / Q000523:psychology; D005260:Female; D033062:Friends / Q000523:psychology; D006801:Humans; D008297:Male; D010379:Peer Group; D057566:Self Report; D012737:Sex Factors; D012801:Sibling Relations; D012919:Social Behavior; D012931:Social Environment; D014427:Twins / Q000523:psychology