Hi queenbee,
wow, what a very difficult situation.

They sound as if they need a full time carer around and it sure does sound dangerous especially if the mother is driving a car if she's doing as badly as it sounds.

Have you ever met any other relatives of your friend? Sisters, children? You've given your friend information as I'm sure the doctor has done as well. The situation seems somewhat drastic to me just from what you've written.

I'm not really sure what to even suggest 'cause I'm not sure if your friend is a full time carer staying and caring for them at home, or if they're totally on their own.

Does your friend stay at home to care for his mother and father or are they living on their own there??

Keep plugging away with the information. Print out some info. and give it to your friend even if they say they don't want it. Please let us know what is happening, it sounds very worrying indeed.