To investigate effects of the timing of initial exposure to maternal depression and marital conflict on kindergarten children's mental health symptoms. Method: For 406 families (of 570 originally recruited), mothers reported on major depression and marital conflict on multiple occasions in the child's infancy and toddler/preschool periods. Mothers and teachers completed the MacArthur Health and Behavior Questionnaire when children were in kindergarten. Results: Children evidenced co-occurring internalizing and externalizing symptoms, although the mix was more toward internalizing for girls and externalizing for boys. Symptoms were more severe among children exposed to either adversity, and these effects were additive. Boys exposed to maternal depression in infancy had a preponderance of internalizing behaviors, but if subsequently exposed to marital conflict, the mix toward externalizing behaviors increased to match levels of clinic-referred children. For girls, the preponderance of internalizing symptoms increased to match levels of clinic-referred children when initial exposure to marital conflict occurred in the toddler/preschool period. Conclusions: It is important to consider both adversities across developmental periods, to distinguish the symptom severity from directionality, and to consider child gender. Prevention and intervention efforts that consider these findings are warranted.
