The current study examined the complex associations among marital status, home environments, and family strain (i.e. income, maternal depressive symptoms, social support, and parenting stress), as they predict preschool children's pre-academic and social skills at 36 and 54months. Findings from the NICHD Study of Early Child Care and Youth Development (N=897) showed that the home learning environment, which was significantly lower among single-parent families, worked as a mediator to explain the relationship between single-parent families and children's pre-academic skills at 36 and 54months. Additionally, parenting stress, which was significantly higher among single-parent families, worked as a mediator to explain the relationship between single status and the home learning environment. Finally, moderation analyses showed that family income is important for improving the home social environment, and the home social environment is strongly associated with children's social skills in single-parent families, but not in cohabiting families. Copyright (c) 2016 John Wiley & Sons, Ltd.