Families' social, demographic, and economic circumstances can have direct and indirect effects on children's development. Structural inequities in access to resources such as education, income, or food can promote disparities in children's health and school readiness. Similarly, children can face more or fewer barriers in their development depending on their race and/or ethnicity. The question addressed in this brief is whether children ages 3 to 5 from families of different backgrounds differ with respect to their health and readiness to learn. The analyses presented in this brief examine the associations between various social, demographic, and economic factors and the extent to which a child is reported to be healthy and ready to learn, using data from the 2017 and 2018 waves of the Health Resources and Services Administration Child Health Bureau's (HRSA MCHB) National Survey of Children's Health (NSCH) for children ages 3 to 5. Data are nationally representative of children in this age range. Key factors that are consistently related to how healthy and ready to learn a preschool child is found to be include: (1) Access to economic resources; (2) Parents' characteristics; (3) Language spoken at home; and (4) Race, ethnicity, and gender.