Well, it sounds she has shoot before. How easy is it for her to handle the wepons, loadin, disesembly and such? Cause hand strength can be a consideration, and recoil. One of the best safety fetures ever is education. So I would teach the kids a little about the guns. Like how to check if a gun is loaded, and how to unload it safely. Not how to shoot yet, but teach them. Then there are other things one can buy, like locks. That is my opinon. And what type of gun she likes and ammo. Maybe she does not want something powerful. A 22 may not be able to make somes exit wound ugly but, a projectile is a projectile, and if she can really shoot well. Maybe that is all you need. My opinon, see what see wants and likes. But for defensive reasons. She may want to take some kind of training, along military or martial arts, so she won't freeze, but instead react in a good state of mind rather than panic state.