Hello Ambika,
Asunra/Exjade is prescribed to children at the age of 2 in US, it is prescribed at the age of 6 in Canada or younger if desferal is not well tolerated.
Chelation usually starts after 12-15 blood transfusions or when the ferrtin reaches 1000. The doctors can decide if they want to start the Asunra before age 2 if the ferritin is atleast 1000, however, I think the starting dosage will be low.
The lower the ferritin at the time of BMT, the better it is.
Good luck with the BMT.