Think about it: Casper the Friendly Ghost is really creepy. Not for the whole “wanting to be friends with people” thing, or even how the guys on Cheers observed that Casper must somehow lose all his friends between cartoons, or that one really warped episode where Casper befriends a fox pup that gets killed, only to have the fox’s ghost show up to immediately pick up where it left off with Casper (that’s some demented stuff right there). No, the fact is Casper is a kid, always will be a kid, and he’s a ghost hanging around for some reason. That’s some prime potential horror right there.
That sort of thing was realized a bit better with Secret.