Why did you post this in the "sex" forum? You'd get more response if you post it in a different forum.
Why are you giving your retirement fund to your brother?
If he is physically dependent on you, you are responsible for what he eats. Bed ridden obese are enabled by those who bring the food. You might be enabling him to deteriorate by doing things for him. Sounds like he might be better off if he is forced to help himself.