Jacobson's Progressive Muscle Relaxation Technique on Children With Leukemia Undergoing Chemotherapy.

The goal of this clinical trial is to determine the effect of Jacobson\'s progressive muscle relaxation technique on anxiety and fatigue among children with leukemia undergoing chemotherapy. The main research hypotheses are; * Children with leukemia who receive Jacobson\'s progressive muscle relaxation technique exhibit less anxiety than those who don\'t receive it. * Children with leukemia who receive Jacobson\'s progressive muscle relaxation technique exhibit less fatigue than those who don\'t receive it. Researchers will compare Jacobson\'s progressive muscle relaxation technique with standardized nursing care on a child\'s anxiety and fatigue.