Social interaction of like-sex twins and singletons in relation to intelligence, language, and physical development.
D000339:Affect; D000367:Age Factors; D000374:Aggression; D002648:Child; D002657:Child Development; D002675:Child, Preschool; D005260:Female; D006128:Growth; D006801:Humans; D007360:Intelligence; D007804:Language Development; D010988:Play and Playthings; D011247:Pregnancy; D012737:Sex Factors; D012919:Social Behavior; D012934:Social Isolation; D014427:Twins