If she likes photography, she'll love an SLR!
It will make her think she is now a good photographer and her friends will be envious of her (and kids love that).

I have my first SLR at age 11, and it was a purely manual camera (an Exacta) which didn't even have a built-in light meter and I handled it fine using a hand held light meter.
Kids today are made for technology and there is very little that daunts them at all.
I think most of them just love complex things and enjoy doing all those adjustments that even scare us oldies.

Get her the camera and you'll have a friend for life.
At least if you give her the camera, you'll be able to buy her stuff for her camera for many years to come, so it will make gift-giving very easy (if not expensive) for many years to come.

A used SLR can be relatively quite cheap.
I wouldn't be buying her a top of the line camera, but I think you should stick to giving her a Nikon, so you can share some of your accessories with her, and when you've finished with something, you can always hand it down to her.