Study Overview: This study tests a way to help people with severe sickle cell disease (a blood disorder) and other anemias (conditions where you don't have enough healthy red blood cells) by using a special kind of bone marrow transplant. The goal is to help more patients get a transplant by using stem cells (special cells that can turn into other types of cells) from donors who aren't a perfect match. The study also uses a method to remove T-cells (a type of immune cell) to reduce risks of a problem called graft-versus-host disease (where the new cells attack the patient's body). Key Points:

• The study involves a bone marrow transplant and requires hospital visits.
• The study lasts up to 24 months, and participants must agree to use birth control during this time.
• Participants will be informed about potential risks, including the possibility of infertility.

Eligibility: Children and adults aged 5 to 40 with certain blood disorders can join. Participants need to have tried other treatments without success and meet specific health requirements.