I'd like to encourage you to not allow your girl to play when you aren't nearby, to begin with.
That I do personally agree with, just to watch what she's doing.
Other than that, I personally don't think you should limit what she's doing in the game at all. I'm a 21 year old male with no kids, so maybe you shouldn't listen to me, and I'd fully understand it if you didn't.
But what I think: You should let her play how she wants. If she's playing what I would do is say: "This character represents you, and is basically your shadow. So you should act in this game how you would in real life." Imo, this would get her in not only the roleplaying mindset, but her own personal mindset for living.
Follow that up by watching her playing and reminding her "That could potentially be a person that you're killing. Do you want to do that?" whenever she were to run into some type of quest, such as DB or other things.
I'd basically act as her jiminey cricket, asking her things like: "If you were to do that in real life, do you think you'd be able to live with yourself?" kind of things. That would give her the freedom to make her own decisions, realize that there were consequences for the aforementioned decisions, give her a better (in my opinion) grasp upon how her actions could possibly affect reality, and let you know how her brain works.
I might be wrong though, not to mention that I'm...well, I'm an alcoholic who is currently inebriated, so I might be wrong (though my typing should be spot on because I quadruple-check it)(and I hope I don't sound like a buffoon) but that's what I would do. It enables her to make her own choices while you're able to monitor what those choices are, so you're able to see what she's learned from wherever (be it school or whatever her in-game choices are based off of) and you'll be able to teach her right from wrong within the same scenario. I'd seen it as a boon towards child-teaching more than anything else.