Why would my daughter do this? Originally she was sticking the kittens head in her mouth, I told her to stop but later she told me she was also licking his head to simulate his mother. What is this?

Many of us are extremely attuned to animals, and in this case your daughter is trying to help out.
I'd tell her you're proud how she wants to help, then explain logically why it is inappropriate.

erm kitty licking is NO good especially after flea baths or if kitty has fleas fleas can carry tapeworms just a heads up.Frankly I would just taell her that if she doesn't stop she'll end up with hairballs.And if she must tongue bathe something tell her that cats prefer to give themselves baths and she can "wash" her arm if she really must do so.

I agree with Vic on all counts. She could end up getting hairballs if she keeps it up.

Trichobezoar is a fancy name for "hairball."

Maybe Willy Wonka made the kitten!

Has anyone else heard of this or anything similiar to this?

I think she's just following the example of a kitten's mother in how to nuture it. She doesn't automatically assume boundaries such as the cat does it but she shouldn't. She isn't deriving any benefit from it other than she feels like she's caring for the kitten.

I wouldn't make it a big deal as long as she's stopped now that you've told her to.