We describe a subset of adults who have survived diseases of pediatric onset. We focused on the portion of that population that obtains at least some inpatient care at a children's hospital. The data reported here can be used to set a lower boundary for the size of this population, and thereby provide valuable data for health planners as well as clinicians. If one includes estimates of expenses across the continuum of care, the financial impact of this growing population is substantial. Public policy discussions should include the medical, psychological, social, and financial needs of this population.