The importance of mutual positive expressivity in social adjustment: understanding the role of peers and gender.

The relations between young children's mutual (reciprocated) and overall positive emotion (PE) with same- and other-gender peers and their social adjustment were explored. Children's PE and peers' PE were observed across the preschool year during peer interactions (N = 166; 46% girls; M age = 52 months). Results revealed that girls and boys had similar frequencies of overall PE and mutual PE when interacting with same-gender peers, but girls were marginally higher compared with boys in overall and mutual PE when interacting with other-gender peers. Girls and boys did not have greater rates of either type of PE after controlling for gender segregation during same- or other-gender interactions. Using structural equation modeling, children's mutual PE, regardless of their gender, positively predicted indicators of positive adjustment (e.g., prosocial behavior, cooperation) and negatively predicted indicators of negative adjustment (e.g., hyperactivity, disruption, exclusion by peers). Children's overall PE did not predict either type of adjustment. Findings support the importance of mutual PE for children's development.