Postpartum depression and low parental self-efficacy (PSE) are risk factors for poor child behavior. Little is known, however, about the course of dual trajectories of cooccurring depressive symptoms and PSE or its impact on children’s socioemotional development. This study sought to identify trajectories of postpartum PSE and depressive symptoms in new, first-time mothers using growth mixture modeling. Results demonstrated a class of women with low risk'' (88.8%) who manifested low levels of depression and high levels of PSE during the postpartum period; a second group of women, labeled early risk'' (6.3%) with high levels of depression that decreased over time but lower levels of PSE that remained fairly stable; and a final trajectory group deemed the ``laterisk'' class (4.9%) with initially low levels of depression and high levels of PSE that significantly increased and decreased, respectively, over the period. Early childhood trauma, parenting stress, and poor parenting practices were associated membership in a high-risk class. Mothers in the high-risk groups reported children with more aggressive and defiant behavior at age 3. We conclude by discussing the implications of our findings for developing effective and sensitive interventions.