It's probably some little 8-9 year old kid, who doesn't understand where money comes from, but understands that s/he's not allowed to have a Kindle, and that hiding it from the parents is probably a good idea if s/he wants to keep it. And chances are, when those parents find it, they will try to return it. They might figure out how to access the note you sent, they might not. Either way, you'll be able to tell because the purchasing activity will stop. Also, doesn't Amazon have some kind of buyer protection so they can reverse the charges and/or lock down the machine?