The aim of this study was to investigate the prospective relations between parental psychosocial functioning and toddlers' sleep consolidation. Investigators met with 85 families 3 times, when children were 15 months (Time 1 [T1]), 18 months (T2), and 2 years of age (T3). Mothers and fathers completed questionnaires pertaining to their parenting stress, marital satisfaction, and perceived social support at T1 or T2, and mothers completed child sleep diaries at T2 and T3. Results indicated that fathers' parenting stress and marital satisfaction, as well as mothers' perceived social support, were related in expected directions to children's subsequent sleep consolidation (T3), with or without controlling for prior sleep consolidation (T2). In addition, all these relations were moderated by family socioeconomic status (SES), such that links were stronger in lower SES homes.