We report the successful transplantation of umbilical cord blood stem cells from a sibling who is human leukocyte antigen-matched to a child with sickle cell anemia. Conditioning was with busulfan, cyclophosphamide, and antithymocyte globulin. Time to neutrophil count >500/microL was 23 days and to platelet count >50,000/microL was 49 days. Full donor engraftment was achieved without graft-versus-host disease. This case demonstrates the potential usefulness of harvesting cord blood from full siblings of patients with sickle cell disease. Routine collection of umbilical cord blood from siblings should be considered for patients with sickle cell disease, and may increase acceptance and use of transplantation by families.