So I was coming out of the bathroom and heard my daughter (9f) screaming in her room. I heard clicking sounds assuming my son (15m) and her were just on the PlayStation. And then I heard her scream again and heard a crash. Still assuming nothing happened I kept cooking. And then she screams a third time.. although it sounded more like a mone. So I went upstairs to see wtf they were doing. As I got to his door it was a little ajar and my son and her were doing the intimate. Neither were fully unclothed but my daughter was asking for more and shit like that. The bed started to squeak and he… I think u get the point. As he was coming out of his room to go use the bathroom, I waited outside his door (my daughter, I assume, was in the closet changing as when she came out, she was wearing her brother’s clothes and carrying hers in hand). I told my wife already about what I saw. She asked me why I didn’t stop them and I had to explain how I froze and didn’t know what to do. I will be telling my kids I caught them at dinner and I’ve ashtray made arrangements to send him to my parent’s home (they r very strict) and we are with our daughter right now in the hospital getting her a v exam. I don’t want to ruin their relation but I can’t have them doing that. Especially at this age in Texas of all places. I am not condoning they continue, and I have been making precautions to make sure it stops. What else can I do?