To feel desperately sorry for her?

[NewMumBGentle]

My uncles long-term girlfriend has a daughter in her early 20s who came to Christmas yesterday. She's a lovely girl who suffers from MH issues and could be described as a bit slow, but very well behaved and pleasant.
Day passes uneventfully until my grandma says she'll take the kids into another room so a group of us can play a trivia based board game, including me, uncle, his partner and her daughter.

This game involves asking questions and on several occasions my uncles partner was making comments such as 'Give her options, she's not as switched on as us', 'she ain't gonna get that answer cause she's not all there' and 'I'll help her cause she's a bit thick.' To which I responded 'X that's bloody awful', she just shrugged it off.
AIBU to feel bloody awful for the daughter. It's one thing knowing your child is a bit slow, quite another to vocalise it to a group of other people in front of her like she's not there. Especially if she has MH issues as it is, knocking her confidence won't help.
She didn't even react to it though, which is the sad part because that tells me that its something she's used to.

I agree with you it's very sad and not going to help her emotionally at all

That's disgraceful. He could have said something like 'X and I will play as a team because it's more fun' rather than degrade her publicly. What an arse. No wonder she has MH issues.

Can you try gently contradicting him? Like every time he says something rude and insulting about her you counter it with something nicer? Without directly addressing the insult you replace it with a compliment? He sounds horrible and like he is far 'slower' than her!

That’s sad. I would invite her over without them there and spend some time with her. She probably has a lot to say just doesn’t know how to voice it, not a surprise if she’s being treated like that.

I think from the OP it was the mother (the uncle’s partner) who made these comments? Agree bloody awful though.

It wasn't the uncle! It was the girl's own mother!!

So yes, vile.

Yeah it was my uncles girlfriend so the girls mother.
I feel awful for her but I'm not sure if I'd be out of line addressing it when they come today if the situation arises. I know critique of parenting is a sensitive topic.

Disgraceful behaviour. One of my siblings has some neurological issues from birth which means it takes him slightly longer than normal to process information and he can come across as slow. If anyone spoke to him in that manner I would go through them and so would our DM. To have to hear that from her own mother's mouth, that's just so sad

This is awful. Why do people feel this is acceptable.

I have much loved uncle with moderate-severe learning difficulties, and I suspect ASD too. He’s in his 60s and has lived a semi-independent life including holding down jobs for his entire adult life. He’s retired now but has his last job for over 30 years. If anyone spoke like that I’d not hold my contempt back.

I feel awful for the poor girl. I'm incredibly intelligent (got a 1st degree) but due to disabilities am a bit slow.. which often becomes apparent during games like trivia as i have limited every day knowledge and have quite slow processing speed when I'm trying to understand and think about things that are outside my scope of interest. So it makes my heart bleed to hear of a mother treating her daughter like that. It would be soul destroying to have to put up with it daily and tbh it's even worse that it sounds like this poor girl is used to it.