Advice for my Grandparents.

My Grandmother is 61 and My Grandfather is 70 years old they are both in very bad shape my Grandmother has Breast cancer and Grandfather has a Deteriorating spine and a bad heart. I fell like they are being abused by their son (my uncle) he is 42 years old and lives on top of my Grandparents he has messed up his life so bad he can't do anything for himself..

Since knowing that my Grandparents has to go to doctor every month to get medicine for their bodies but the thing is my uncle is a pill head he ends up stealing their pills and taking them all away from them and treating them in return like straight Shit.

My Grandparents are thinking bout packing their stuff and moving leaving uncle here to take care of himself. They are gonna move and leave their house cause of some bum that sits on his ass and does nothing but take from them I don't think this is right and fair on them he is just abusing them and he does not care if he hurts them or if they do without and hurt. What would any of you advice to do?? Any help will be appreciated! Thank you!