AIBU to think my 11-year-old is not to blame here?

I'm not sure if anyone else has mentioned this but I'd also want to make sure that the glass in my parent's house internal doors was safety glass in future. If they had safety glass fitted in the door then he would not have been hurt so badly. Why would your parents have dangerous glass in their house with young children running around?

Seems like the ideal punishment for your 13 year old would be not to go to his grandparents again.

Ultimately your Mum is to blame for not supervising the kids especially when one is autistic with older son coming in a close second for blame. Where was she when your son was trapped and presumably shouting/screaming for help?

Unfortunately if there is favouritism, you have to keep them all away. It's very damaging.

13 year old knew exactly what he was doing. I would be having serious words.

The 13 year old was to blame but really couldn't be expected to foresee the seriousness of the consequences.

I also wonder that the grandparents weren't aware of any of this happening. I get that at 11 and 13 the children wouldn't be under constant supervision but you'd have thought if the 11 year old was hammering on the door, enough noise would have been created for them to intervene.

13 YO to blame equally with your mum. Where was she when this was happening?

And who the fuck blames an SEN kid over an older, neuro typical teenager?

Your mother/parents seem like a negative influence on your children. Are you financially beholden to them or have a house on their land or something? I would be seeking to massively restrict their time and influence, if they were my kids. If your oldest is unremorseful and all “jack the lad”, “not my fault” about this, I would be worried at what he might get himself into in the future. You don’t want to raise a right little psychopath/sociopath in the sense of causing harm to others but nothing is ever their fault. Keep a very close eye!

Your 13 year old was bullying his ND younger sibling. That’s horrible in itself, regardless of the outcome.

That said, I suppose to fairly assess his blame for the injuries you should ask yourself “how forseeable was it, to DS13, that DD11 might panic and do something damaging?”. Maybe he just thought he’d get upset and cry (still bad, obviously) or maybe he knew that DS11 is prone to doing slightly crazy things when under pressure and wanted the entertainment- if so, that it extremely shitty behaviour even if he didn’t expect a serious injury to occur. Either way I’d be cross but more cross in the second instance obviously. Remember you are the mum and you are better placed than grandma to judge your eldest son’s motivation in this as you know him better.

Agree with other posters than ds11 will remember forever if you blame him.

This, what is it recently with threads about 1 dreadful child and the poor perfect sibling, which results in the op cheering on the posters calling one child a dick,brat, awful, selfish etc etc with the pitchfork cries of “PUNISH THEM!! PUNISH THEM!!!”
?

It sounds like siblings messing about and having a bad outcome. 13 year old should be making a proper apology to 11 year old, no sorry but.
the in laws on the other hand I would be stopping them seeing any of the kids until they can treat them all equally. Buying gifts for one child and not the others is out of order and is horrible for the younger kids. As their mother you need to step up and put a stop to this.

13 is old enough to understand the dangers and know exactly what he was doing. I've been a 13yo with an annoying 10yo brother and if I'd done something like this . . . I can't imagine what my parents would have done. I would not have been forgiven.

Same here.

However it has surely blown over by now, they are both kids. Your mum should be more realistic about this and not make such a big issue of it.

I hope the cuts heal well.

Just sounds like siblings messing around, it was an accident. No need for all the unpleasantness towards a 13yo as demonstrated by previous posters.

13 year old needs meaningful consequences without interference from your mother. She needs a few consequences herself for the favouritism. The 11 year old panicked and is not to blame. Thank goodness it was not worse! I am sure they all got a fright today, time for a reset.

OP hasn't mentioned a husband or partner (I think); is she perhaps very very reliant on GPs for childcare and daren't rock the boat?

no it isn't the favouritism stops or the visits stop tout court.

If that's the case your parents are undermining you.

Send your oldest to your parents, they can keep him and them safe, when they call you to day they've been hurt tell them that hes the fave and deal with it, your other kids aren't getting sliced up. When they moan he doesn't listen....just say yeah.....you made this. Then hand up. You eldest could've killed your 11 ye old.

They're your kids.

It has nothing whatsoever to do with your mother if you choose to punish him.

Why didn’t grandma step in to stop the tomfoolery?

What do you mean its hard to do so?
He did something to an autistic 11 year old that caused them to panic and as a result of that they were injured.

You dont need your relatives approval to punish him. You are his parent. Discipline him.