It sounds like the LW's son has learned not to have any opinions except his mother's, and that is as tragic as what is happening to the daughter. Perhaps more so, because she will probably be able to get out and lead a normal life someday.

yeechhhhh. The other thing I thought of when I read that letter was, what kind of relationship must her kids have with each other?? I love my brother more than anything, and we always got along growing up. I didn't understand my friends who hated their siblings and wished they were only children. We each think the other one is our parents' favorite, and my mom insists she doesn't have a favorite, but it's mostly joking.

I can see what aspects of him my parents prefer, but that's their fault not his, so it hasn't hurt our relationship. Likewise, I know there are things about me and the way I live my life that they prefer to his (he's smarter, cooler, and has a better job than I'll ever have - he's more "Braggable" to other parents; I handle money better. He's more forthcoming and comes to them for advice more, but I'm more independent. I control my temper better. Etc.).

There is no way this girl and boy can possibly have a relationship, and that makes me sad. I don't know whether the son plays up his "good kid" image to the mom and relishes evilly in how much more his mom likes him than his sister, or whether he feels horribly guilty about mom liking him better, but either way it's totally toxic.

To the OP: I'm so horrified every time I hear of a family in denial over abuse. I'm sorry you had to go through that. A good friend of mine was sexually abused by her older brother when they were young. She finally told her parents (after her attempted suicide in college). They don't deal with it at all. She's in therapy on her own, but I don't think her parents ever spoke to her brother about it. They just don't want to know. It's horrible.