if I buy 1 day ticket, can I enter in the morning, then go out and re-enter after 2 hours?

We'll bring a young kind. He needs a rest (take a nap, etc), so we have to get out from Disneyland for 2-3 hours for him to take a nap at the hotel, then come back to Disney;and again. Or do you have a rest lounge inside Disneyland HK?