Question...
May I ask ... why are you or why is she set on a semi-auto? There are MANY VERY RELIABLE revolvers out there that are just as, if not more, concealable as a semi.
If she is very petite and having trouble racking the slide as you say ... not that she can't do it but that she is having difficulty with it ... then I would agree with ZeroDefect and Cocojo and get a nice clean light revolver!
God Forbid that this young lady is ever required to use the gun and in the heat of the moment cannot get the gun to cycle properly. I REALLY like S&W revolvers and would recommend a J-Frame Airlight.
You need a gun that, when you're attacked, can be operated and used without thinking.
HOPE IT HELPS! Take Care & Be Safe!
NJGunOwner81