AITAH for telling my brother that his father is a rapist/pedophile?
To start and make a long story short before the main issue, in 2020, I found out my stepdad had sex with a 15-year-old when he was 22. He was sent to prison and then a registered sex offender for 15 years after his release. I told my 15-year-old brother about it, then 12, in 2023. Now for the main part. So a couple months ago there was a fight on the farm my family lives at that involved everyone except me because I don't live there. My stepdad had left the farm in anger which led to the rest of my family talking about the fight (Two brothers, 21 and 15, sister, 19, and mother). The 15 YO brother got pissed and told them they were living with a sex offender and told them that I was the one who told him. My mother gave them some bullshit excuse that he was drunk and didn't know her age. Keep in mind that when I asked my mother about this back in 2020, her words were, "He claims he didn't know how old she was, but I think that's bullshit", contradicting words, clearly. My sister isn't buying into it, but my 21 YO brother is, and he told me that I probably shouldn't have told a 12 YO that information. I don't know about all of you, but I knew about heavier topics when I was FIVE, as did my brother at older, the kid isn't stupid. Plus, older people fail to realize that kids these days and long before absorb FAR more things that they think. My 21 YO brother also thinks it needs to stay in the past because it happened before we were born. A pedophile is a pedophile to me, no matter the passage of time. All to say, everyone except my sister and youngest brother thinks I'm in the wrong. One final piece of context, I'm the only kid who isn't bio-related to my stepdad. I don't believe I am in the slightest, but I've got to ask, am I the problem? What are your thoughts on this?
Edit: Forgot to mention I'm 22, not that it's relevant