It is unfortunate to have such condition in family . But any haw we have fight bravely.
I would like to advise to start Ayurveda treatment for the maintenance and to lead relapse free life .
Put him on Balanced diet give him more milk and cows Ghee which gives the strength to the bone marrow
Give salt in very less quantity and stop sour think (Pickel , tamarind ect.)
keep him away from all kind of infections so that his immunity system can get strong .