This study is testing a new way to do a stem cell transplant, called RIC HIDT. In this trial, patients will receive a medicine named Fludarabine and a type of radiation called TBI (Total Body Irradiation) before getting the transplant. The transplant uses cells from a family member whose blood matches at least half of yours. The goal is to see if this new method is safe and works well.

• The study requires a related donor whose blood matches yours at least 3 out of 6 possible ways.
• Participants need to have a blood cancer that needs a transplant and have a good performance status (KPS ≥ 70%).
• There are health requirements you must meet, like having a good heart and lung function.

If you qualify, you will receive the new transplant treatment and be monitored closely. The study checks how your body responds to the treatment. Consider the time commitment and whether you meet all health criteria. There might be risks involved, and it's important to discuss these with your doctor before deciding.