Abstract: The Supplemental Security Income (SSI) program provides income support to a growing number of children with disabilities in the United States. Many SSI recipients also receive publicly-provided health insurance through state Medicaid programs. In this paper, we analyze the relationship between SSI and child outcomes by exploiting discontinuous changes in SSI eligibility for low birth weight infants using a regression discontinuity approach. We study the effects of the child SSI program on hospitalizations and mortality, child development, maternal labor supply, parenting behaviors, and maternal depression using data from the ECLS-B, HCUP and Vital Statistics. Our findings contribute to a growing body of evidence linking investments in early child development and later outcomes.