The study uses a unique State-level longitudinal database linking administrative datasets on WIC and Food Stamp Program (FSP) participation, Medicaid enrollment and claims, and child abuse and neglect reports in Illinois. The study will examine the individual effects of WIC and FSP participation as well as their combined multiple participation effects on a wide range of child health and well-being outcomes. The study will correct for the potential selection bias using several statistical approaches such as sibling fixed-effects models, Heckman two-step procedure, and random-effects models.