I have to agree with what everybody is saying. If you look closely at the pictures, the boy does have his arm behind Tigger the entire time. He also has this look on my face that I can't depict. Its like, foreshadowing something. If the boy was about to take advantage of finding the back zipper, Tigger had every right to defend himself.
Now, I'm not saying that Tigger should hurt someone, but he could try to step away or wave his arm. Maybe Tigger meant to wave his arm instead of punching the boy. I don't know myself, but I would think its hard to see through those costumes, especially if you're trying to defend yourself.