I posted this last year in another thread.
For 12u and older, I recommend a 11.5" to 12" for a middle infielder, 11.75" to 12.25" for 3B/P, 12.5" to 13" for 1B/OF, and 32" to 33" circumference for catchers. Don't be afraid to spend a little coin on a glove. I see too many girls swinging a $250 bat that have a $40 glove and $30 cleats. With Wilson, Demarini, Rawlings, Easton, Worth, and Mizuno, a bit of the cost is due to the advertising. Don't be afraid to check out gloves from Nokona, Zett, SSK, Kazuma, and Glovesmith. I think you get more for your money with these brands. I prefer the gloves made in either the USA, South Korea, or Japan. They feel better, retain a pocket, and last longer overall. The best gloves are made out of USA Steerhide, Bison, or Kangaroo. When your DD puts her glove away, make sure she places a softball in the pocket; she should not let her glove go flat.
Len