There is no advantage to adopting your brother, given his age. If your father is the custodial parent, all he has to do is give you a power of attorney to allow you to make all decisions a parent would normally make for a child. That would allow you to care for him and at the same time not destroy the parent child relationship between this mostly grownchild and his father. Since the boy will be living with you, you can take him as a dependent on your taxes and for health insurance purposes.
Answered on Mar 02nd, 2016 at 4:00 AM