My ex husband had an affair which resulted in two children being born. The first one was born a week after ds1 and the second two weeks before ds2. My children don’t feel comfortable being involved with siblings so close in age to them that were as a result of an affair. I’ve recently had a conversation with his mother who tells me it’s not that unusual and my children should just accept it. Aibu to say it is unusual to have half siblings so close in age and that they shouldn’t feel pressured to talk with these people. All are now adults. His mother wants them all to get together.