Hopefully OP is playing an April fools joke on us, because no sane person would shave a child's head without permission. I wouldn't let your daughter be alone with him anymore.

He never would be left alone with my child again. That is not acceptable. Maybe he would find it funny for bullies to make fun of her and her eventually harming or killing herself because of it. Extremely childish of him.

When he's sleeping, shave his head bald for a "laugh". Joking aside, if she's not too torn on it, I wouldn't be too upset, as long as she's happy and I'm sure she's beautiful either way, it shouldn't be a problem.

That's pretty funny tho and she's a kid it won't affect her that much

I can't even imagine how upset I would be. He would never be allowed to watch her again and possibly not even allowed AROUND if he did that without consent. Not only will it most likely attract negative attention, it completely disrespects you to do something like that to your child without your approval. If he does this "for a laugh" and obviously doesn't respect you as her parent, what else is he willing to do?

How old is she?

It's a nice way to be sure you won't ask him again.

Depending how she took it it can be a huge trauma. I hope she took it as a joke also...

Grandparent goals. He had them.

that's hilarious. he is gonna be the favorite grandad