Wow, I'm impressed that you read the whole thing! I posted it mostly just to get it out of me (just seeing it in words made me doubt myself a little less), but I'm also very glad to have your feedback!
I'm very sorry to hear about your second cousin. I read somewhere that autistic children are more likely to be abused (something like one in five autistic kids become victims of abuse at some point). I've always found something so exceptional and wonderful about autistic children...even if they have a lot of problems, it always seems that there's something beautiful and unique inside that it'd be criminal not to help them express--which is why it boggles my mind that so many of us are abused. But I guess it's easier to dehumanise what's "different." Perhaps, though, as they get older, your second cousins will form a supportive bond that will help them endure their situation...and I hope you are allowed to be a part of their support system, as well.
It's so, so comforting to know I'm not alone. I mean, I know I'm certainly not the only survivor of child abuse out there, but...actually making contact with someone who has experienced these things too...it makes me feel a lot less ashamed of it all, and that is a pretty big step in the right direction!
Best of luck to you, too!