tx, here's what I would recommend... go to ebay... sporting goods... archery... bows... then type in mathews genesis under search. You can buy them from $100-$150 on ebay from what I have seen. That bow has very low poundage, which increases when you draw it back. It has no set draw length, basically however far you need to pull it back to hit your anchor point. It's advertised as a bow the whole family can shoot.
Otherwise you might want to take her to a pro shop and have her shoot a few different set ups there. Make sure you know what she is capable of before spending your cash.
ArcticBowMan's Hunting Photo's