I don't get this (MySpace-related question)?

I am 35. I have a step-nephew (18) who is very friendly, polite, smart, and articulate in person, but on MySpace he has a totally different persona -- as that of a gang member and druggie. Now I don't know which persona is real. I know he thinks his step-grandfather (my dad) hung the moon, so I don't know if he just puts on a front when he comes over to his house or if he puts up a front on MySpace to impress his friends. Which persona am I to believe is the correct one?