Few questions

I've seen the movie a year ago but I haven't seen the end, so I've tried to find some information about real Katie but no luck. I was wondering if anyone here can answer my questions or at least some of them.
1. How does the movie ends?
2. Was Katies real identity ever revealed? I know there ar epictures of real Katie, but no real name can be found.
3. Where is she today?
4. Was she ever socialized and able to live on her own or at least with some guardian?
5. What happened to her parents and why was she treated like an animal? In the movie we see her older brother raised properly (as much as possible considering their parents).

Thx and cheers!

Fool is the man whose madness does not mach the madness of most.