like i said the sig 522 and 15-22 are very reliable. as with any long gun a backup handgun is a good idea. i have no experience with the new ruger lcr 22(8 shot .22lr) but it seems like a good backup gun for her. plus it would be fun to shoot and practice. only down side is the sub 2" barrel, not sure how much penetration the .22lr would get in that case.
im actually thinking of getting this for when i don't want to ccw:
4" barrel, .22lr to plink with, .22mag to ccw with. this naa revolver would be for backup or when i don't want to ccw my glock 19. im also thinking its great for my boat survival box incase i break down i have a .22lr to get a bird or something. i always keep 200+ .22lr rounds in that box.