Once they're actually moving towards the door, Donnie clings to Leo in eager anticipation, at least until they're inside.

He doesn't budge once he's set down, too busy staring. It's not lined from floor to ceiling in books, but it's still a lot of books. Where does he even start? He's too young to have such a dilemma!

While Leo's trying to work out where things are, Donnie seems to have decided that the only way to do this is start at one side and see how far he gets in finding anything interesting. Already it seems he's forgotten about the not wandering off, but at least he can't get too far.