I am not familiar with the Ruger American but I am familiar with the Ruger 10/22. The 10/22 has an adjustable rear sight for elevation. Check the rear sight on the American if it is adjustable for elevation then the front sight is not too big but the elevation is adjusted wrong.
The sight picture you want is to have the front bead centered in the valley of the rear sight and the point of impact sitting just on top of the front bead. When shooting your daughter should focus on the front sight. This is how I have my 10/22 set up. The Ruger American may be different.
I'm just trying to help