I have a 16 year old sister. She was on Facebook and then deleted her profile. She deleted her profile at about the same time she went from being semi-awkward early teenager still shaking off her Russian accent (we adopted her) and became one of (what I am guessing based on her friends and the things she does) the coolest kids in her school.

She is probably doing lots of things that I don't want to know about. That's cool and Facebook gets in the way of doing that.