Evidence of reactive gene-environment correlation in preschoolers’ prosocial play with unfamiliar peers.

The development of prosocial behaviors during the preschool years is essential for children's positive interactions with peers in school and other social situations. Although there is some evidence of genetic influences on prosocial behaviors, very little is known about how genes and environment, independently and in concert, affect prosocial behaviors in young children. This study of 126 twin and sibling pairs examined 5-year-old preschool...