 RATIONALE: - Relapsed or refractory Neuroblastoma NBL carries a very poor prognosis and children with relapsed NBL have an overall 3 year survival rate of 10. Hematopoietic Stem Cell Transplant from a different donor allogeneic, is a form of adoptive cellular therapy , such that infused donor cells find host tumors as foreign and fight them. After transplant, the donor immune cells i.e. T cells, NK cells mediate Graft versus Tumor GVT effect and may stop tumor from recurring. Also,reduced intensity transplants lead to minimal toxicity and less risk of mortality in heavily pre-treated NBL patients. 