We addressed the question of whether mothers of conduct-problem (CP) children differ from mothers of non-CP children in their awareness and coaching of emotion, and also examined whether mother's awareness and coaching of emotion is associated with better peer relations in CP children. Meta-emotion philosophy, assessed through audio taped interviews, and preschool children's peer relations, observed in same-sex dyadic interaction with a close friend, were investigated in families with CP and non-CP children. Results indicated that mothers of CP children were less aware of their own emotions and less coaching of their children's emotions than mothers of non-CP children. Moderation analyses revealed that children's level of aggression moderated the relationship between mother's meta-emotion and children's peer play. For both aggressive and nonaggressive children, higher levels of mother awareness and coaching of emotion was associated with more positive and less negative peer play, although effects were stronger for families with nonaggressive children. These data suggest that both aggressive and nonaggressive children can benefit when parents are more aware and coaching of emotion. Implications for the development of an intervention program aimed at improving parental awareness and coaching of emotion is discussed.