I have a toddler who is much loved by my DH and myself and the grandparents. My husband's brother has autism and lives in assisted accommodation. He has trouble regulating his emotions and sometimes has aggressive outburst and once was even in court for threatening a staff member (where he lives) with a knife. My DH previously described him as a "creepy uncle" of the family and his cousin mentioned that his teenage daughters feel uncomfortable around him. I mentioned to my DH previously that I would not feel comfortable with his parents babysitting alone if his brother was around. Although they are lovely people they are in their 70s and 80s and they could not protect our DC if the uncle had an aggressive outburst. My DH agreed and said we'll just tell them that.
However last weekend we were visiting the grandparents and MIL mentioned that the uncle (DH's brother) is staying with them next week as some work is being done on his accommodation and whether it is okay they bring him to come babysitting (the babysitting has been scheduled for a couple of weeks, it is not a regular occurrence). I sad "I'm not so sure about it" and looked at my DH hopping he'll explain, but he just said "yes, that should be fine". I was really upset about this and when we were alone reminded him about our previous agreement (he said he forgot) and he said that he'll talk to MIL. After talking to her he said she was very disappointed and DH was very sad and told me he feels torn and like he's betraying his mum and brother. I obviously don't want him to be sad, but what should I do?