[quote=@Guess Who]
I think the only thing Beacon isn't aware of is the more shady parts of Robert's history (i.e. that he stole food, money, etc. to survive). Actually, no one knew about that other than his original team and they're gone now. I don't think he's even told anyone that he's an orphan other than Sand during the team's current mission.
[/quote]

Technically speaking there's no actual proof of what Sapphire went through as a child but with a quick background check it wouldn't be difficult to piece together what he home life was like. A couple of 911 calls, an unusual number of trips to the doctor etc.

I would assume that Ozpin is either aware of her past or at least suspects most of it but chooses to let it alone unless it becomes apart of something that effects more than just Sapphire.