Seeing that your wife was a Marine instructor, I am curious if the pistol stance your daughter is using is the preferred one. I was wondering since I find it more comfortable (and stable) to stand with my left foot forward and right shoulder back instead of being squared up to target. Is there an advantage to being squared up to target?
I have always been taught, and now teach, isosceles. It was also standard when I was in the Marine Corps. The same applies to my wife. Rather than plagiarize some one elses work, here is a pretty good article on the two most popular stances, Isosceles and Weaver.