you did the right thing---and I suspect that she knows it which is why she hasn't outed you to other people---the big question now is will she do the right thing to protect her daughter and leave the abuser? Her excuse for him, that the 3 year old daughter knows so much about male anatomy because she watches porn with her SO is laughable----anybody who exposes a three year old to pornography assuming that's what happened ought to be banned from being around children---that kind of behavior is another form of child abuse. In any event it wouldn't be the first time a mother has made excuses for an SO who abuses her kids---hopefully the authorities will or have stepped in to stop matters. You have done all you can do to help the little girl--good for you