The weight and size are actually what makes the fullsize .45s a joy for women to shoot. The recoil is smooth and absorped by the length of the barrel so you get more of a "swaying" muzzle flip. Compared to 3-3.5" barrels that flip quickly with no weight on the front.
Anyway, as already mentioned, let your daughter go handle the guns. I've seen many guns that look great on paper, but when I handled them, it was a big fat red X. I'm a 5'3" gal with skimmy small hands and I love to shoot the SA 1911. The grip is just on the verge of being too big (back to front). We have some thin checkered rubber Pearce grips that are slim and make the grip more accomodating. I might take off my rings just to get extra snug grip and not scratch up the front grip frame.
I do all shoting and handling single-handed and I have to move the gun around to hit the mag and slide release, but I can work the safety just fine. Your daughter will probably have an easier time than I
Like the guys said above, take your daughter, and don't let any of the idiots standing around comment and make her nervous. That stuff sticks in a lady's mind and will make her feel like she's forever being watched and/or scrutinized. To some ladies, its a challenge, to others, it's crushing.
Edit: I see you're choosing a 9mm, then the shooting will be even better. As for the weight, practice will help her hold and shoot it.