One of her legs may be stronger than the other by now. Clipping in/out is half mental. Once it becomes second nature it is hard not to unclip unless there is a mechanical failure with the pedals. Also helps to be proficient at unclipping both feet perfectly.
Besides clipping in to my road bike (SPD-SL) I also have SPD clips on my mountain bike. When I do trails clipping/unclipping happens a lot. Great practice. You may want to try some Shimano SPD clip pedals as they are easier to clip/unclip.