Son calls dad 'pathetic loser' in front of family to defend sister, family is split.

My (31M) father (59M) got a divorce from my mother when I was thirteen because he cheated. My sister (28F) Lily who was ten at the time caught them and told my mother. My dad ended marrying his affair partner but he's always resented sister for this.

My mother never forgave him and she never spoke to him again outside of co-parenting. My dad felt as though he owned my mother and he caused a lot of problems when she remarried and was able to have a child with my stepfather when she suffered many miscarriages with my dad.

He gets visibly very moody when I talk about my stepfather, half sister from my mother or my step siblings.

Lily is also divorced from her ex-husband Daniel (32M) but they're still close friends. They share some cats and constantly hang out together and Daniel still comes to our family events sometimes because Lily feels safer with him around.