Husband wants me to delete his family on Facebook

My husband and I have been married for 8 years. We have a very strong relationship but his family have always been very like warm towards me, I think due to the fact that I’m an immigrant. I’m now a citizen but my family all still live in my country of origin which makes things hard.

My husband and I have three children. Our oldest has diagnosed moderate autism and my husbands family have always been very cold towards him which bothered me. We only see his family twice a year so it’s never been that big of an issue or bothered my son greatly but it’s gotten to the point where I no longer want to go to holidays etc due to the way my kids and I are treated. My husband has said in recent years that he feels like he has become an outcast to them also by showing up is the right thing to do since we’re invited every year.

His cousin and him were talking the other day and his cousin mentioned to him that his aunt, who has been a mother figure to him most of his life, said while a lot of family members were present that she believes autism is a made up “disease” and our son is the way he is because of bad behavior we have allowed and our “lazy parenting”. I was infuriated obviously but not surprised because they have always been vicious and made remarks that hurt towards me but this is the first I’ve heard about my five year old. My husband on the other hand was so so hurt and immediately blocked the phone numbers of his whole family and unfriended all of them on social media. He has asked me to do the same which I will but I worry that my husband will get over this and want to reconnect and refriend them all etc but if I burn this bridge that will be it for my relationship with them. I feel they will accept him back whenever he is ready but any semblance of a relationship I had with them before this will be gone.

Should I still unfriend them all and block their numbers or should I hold off and let my husband cool down?