Minerva McGonagall: Albus, do you really think it's safe, leaving him with these people? I've watched them all day. They're the worst sort of Muggles, imaginable. They really are...
Albus Dumbledore: The only family he has.
Minerva McGonagall: This boy will be famous. There won't be a child in our world who doesn't know his name.
Albus Dumbledore: Exactly. He's far better off growing up away from all of that. Until he's ready.