Granted, I have boys - but I say let her do it.
I had a girlfriend who had a daughter who was 'hairy'. She just happened to be harrier than the average 9 y/o at the time... and she begged her mom. Geez, I was over there one day when she got off the school bus and came in just sobbing after being made fun of on the bus. I mean just unconsolable crying.
Her mom and dad just wouldnt budge. I even said to my g/f later - what is wrong?? Who cares, just let her do it!! They were like no, not until (I think they said) she is 14! By 14 the girl would look like a monkey - seriously.
So, she stopped wearing shorts or skirts ever - in fact she's like 15 now, and I dont think she wears them even now, and she is allowed to shave - but she's THAT uncomfortable in her skin because of all that.
You know, I wanted to pull her aside give her a razor and tell her 'just do it' - honestly.
She ended up, i think the following summer - just doing it. And she was in HUGE trouble...but they did let her do it after that.