Paralytic condition of father handover to brother

my father is 85 years old and paralytic, unable to move without any help,can speak.is living with me for one and a half year, i took lot of care with all his needs including medical treatment,but now i m going abroad with my family permanently, so i have to leaving my father. i have only one brother living in the my father property and not willing to keep him, i doubt he and his wife may hurt, even life threat to my father due to his property i.e. a small house. and i have no good and healthy relationship to my brother and at this age my father do not want any complaint type to any one against my brother , my father also diagnosed as odd behavior, so i m very much worried about my father and what i should do?