I'm not sure what to do when my 23 month old goes and stands on the cats tail. It's out of character for him, because he is usually so gentle with animals, and he speaks so softly to him. But then sometimes, he sees the cat's tail, and goes and gingerly steps on it, and the cat yells, and he busts out laughing, and tries to do it again. I don't know how to make him understand that it hurts the cat and it's not a fun game to make the cat yelp. Any tips would be greatly appreciated.