My sibling asked me to 'come out' from a specific place, and I, jokingly replied 'Ok, I'm bi!'
no reaction
Not even from my parents who were in the room at the same time (for context my younger siblings were like 10 or something)
Later, I causally mentioned in conversation that I was bi and nonbinary, so my mother told me 'everyone's a little bit bi' and that being nonbinary was a mental health disorder or possibly a figment of my imagination, although they're a bit more supportive now, I think they still think those things.
Oh, and I told my friends and they were like 'that's cool, I'm LGBT+ too!'