Kids dont go off the derech overnight. It is usually a slow process, Skipping a minyan here, cutting school there, a movie without the parents knowing etc. Parents should hopefully be able to see the signs before it is too late. I should know because I have boys considered “at risk”.
The way to handle it is not to turn a blind eye, and I am Chas V’sholom not saying that anyone here did that (I haven’t read most of the posts). Fighting and yelling doesn’t work. Ignoring it doesnt work.
What I have found that seems to be working for me, is that the parent (i.e. me) needs to accept the fact that their child may not, at least at this point in time, want the same level of Yiddishkeit that is expected. That needs to be OKAY. If the child knows that there is love no matter what, then there is a fighting chance (trust me, it took me a while to understand that myself). Once the child feels safe at home, there can be a gradual (and I stress Gradual) change. None of us are perfect and we should judge these kids as favorably as we can. Afterall, don’t we want to be judged the same way by Hashem (Avenu Sheh Ba Shamayim)?
B”H my sons, while still a bit away, are now moving closer to where I want them to be instead of further away.
As far as the girls go, I have no experience with that, But what I have read as to reasons why they cant be talked to sounds ridiculous to me. To save one N’shima is as if you saved the world, right? I dont think it should matter what the neshama is wearing.
May Hashem gave us all the strength to contiue to fight this battle.