Preparative regimen using total body irradiation (TBI) and cyclophosphamide: 1. on day -6 and -5: cyclophosphamide is given, 2. on day -4, -3, -2, and -1: TBI is given, 3. on day 0: stem cell or bone marrow is infused. Alternate preparative therapy for patients not able to receive TBI The chemotherapy (cyclophosphamide and busulfan) is given with the intent of destroying the bone marrow, eliminating any cancerous and preparing for the transplant of the donor's blood stem cells by suppressing the immune system. l. Ten days before the transplant (Day 10), subjects will be admitted to the bone marrow transplant unit and placed in isolation to reduce exposure to infections. Isolation will be continued until adequate numbers of cells are present in the blood to fight infection. 2. On day -9, -8, -7, -6 busulfan is given. 3. On day -5, -4, -3, -2 cyclophosphamide is given. 4. On day -1 no therapy is given (day of rest). 5. On day 0 the donor stem cells are given intravenously. Additional cells may be given on day +1 or 2 as needed. Transplant: Subjects will be admitted to the bone marrow transplant unit and put in isolation to reduce exposure to infectious agents. During this time, they will receive the preparative treatment outlined above. Once they have received the preparative regimen, stem cells will be obtained from the donor and given intravenously. The new stem cells will replace the bone marrow that was damaged by the treatment for the cancer. Isolation will be continued until adequate numbers of cells are present in the blood to fight infection. Subjects will then be transferred from the bone marrow transplant unit and discharged from the hospital when medically ready. Subjects will be expected to return for follow-up to the bone marrow transplant clinic at specific dates as determined by their physician.