Difficult relationship with dad’s side of family

My dad died 4 years ago, we always had a difficult relationship with his side of the family. Personalities do not match and a few incidents happened. Since he died it got worse. There is contact but it remains to pleasantries.

I’ve always felt sad about the situation. We have good contact with mum’s side of the family, I feel sad we can’t have this on dad’s side.

Besides all that my brother does not seem to understand the tension in the family and he likes to makes ‘jokes’ in a groupchat that makes it even worse…

I feel like this family is drifting apart from me and I can’t do anything to stop it…

I’m also afraid they dislike us because of my brother’s inappropriate comments…