Same here. If she's grossed out, invite her to shave. It's not a big deal like when we were girls (waaaay back when). With a little help from you, she won't have any nicks or cuts.
She's really too young for waxes or chemicals. I'd let her shave until she's old enough to wax.
Another alternative is laser. I had it and it kept me hair free for five years. I have very manageable thin, light hairs now. It works best on light skin with dark hair. It's expensive, but I've seen home units on Amazon that purport to be good. I probably wouldn't go there unless I heard good reviews from someone trusted.