I have known since i was 10 that my dad was gay. He was completely sexually attracted to men with one exception, he was romantically to my mom and just my mom. The only time they ever had sex was to have me. since he wasn’t sexually attracted to my mom they had an open marriage. And thats where i thought it ended, until a couple weeks ago. My dad unfortunately passed away on Christmas eve when i was around 10. So i was visiting my mom we were chatting about dad and eventually the topic went to their open marriage. That was when my mother just said like it was no big deal “Yeah i had to cheat on him to convince him to have an open marriage.” I was shocked so i just switched the topic and went home soon after. Sorry if this was short.