How do I best go about making clear that I (21M) don't plan on becoming my girlfriend's (21F) disabled brother's (23M) caretaker?

I have been dating my current girlfriend for two years now. She has a high functioning autistic brother, who I think is a good natured kid but has been absolutely spoiled rotten by their mother, who has done everything for him throughout life. He throws frequent tantrums, refuses to clean up after himself/maintain basic hygiene, and spends all his time playing video games and doesn't have any career goals.

I visited her family over Christmas break and I have a suspicion that her parents want to dump their son onto me, especially after they learned that I have a high paying job lined up after I graduate from college next spring. I'm not sure if it's just me being paranoid, but they keep asking me rather pointed questions like the size of the apartment I'm living in, etc. and have this generally sweet attitude towards me that wasn't present before.

I told my girlfriend about my concerns and she said that she thinks her parents probably expect her to take care of her brother although she hasn't talked about it with them. She said she doesn't particularly want to but if she "has to" she'll be strict with him. I wasn't really satisfied with this answer but I didn't press the issue further. I really like her and I feel bad about this situation but I definitely do not want her brother living with me down the line. How should I make this boundary clear?

tl;dr: I suspect my girlfriend's parents want me to take responsibility for their autistic son, I do not want this. How do I make this clear to my gf in a sensitive manner?

Submitted December 25, 2021 at 03:28AM by Altruistic_Side_197 https://ift.tt/3EmWQNT