I have often thought about hiring a helper. I haven't yet simply because I can't set up my dayhome the way I would like until our family moves out of our basement, lol.
I would enter into it carefully, since it's a friend/neighbor. Should things go sour.... awkward!! But it could be beneficial to the both of you, as you get an extra pair of hands and eyes (and who doesn't need that??) and she gets the experience she needs also. Perhaps if you can go into the deal without "depending" on her, necessarily. That way if she leaves, you aren't left high and dry expecting certain things?