Preliminary Data: The investigators' team completed a feasibility study of yoga in 11 children with cancer or HSCT recipients meeting similar eligibility criteria as the proposed study. In short, these results demonstrated the feasibility of individualized yoga and suggested several design changes to enhance compliance with outcome ascertainment. The investigators found that the mean ± standard deviation for the baseline and day 21 proxy-report PedsQL MFS general fatigue scores were 46.4±26.8 and 55.6±15.5. These scores are much lower compared to fatigue scores observed in two studies of healthy children in which scores of 88.8±12.3 and 89.3±13.3 were described. This data suggest that fatigue is expected to be very severe in our patient population.