If she is having a difficult time shouldering the gun and/or shooting it because the stock is too long making the gun muzzle heavy, finding a stock (and/or shorter barrel) that would fit her better would be more beneficial than getting one with a shock absorber because she could hold/use the weapon more efficiently.
Just for example, a 28 inch vent rib turkey barrel is a lot more muzzle heavy than a standard 18.5 inch barrel.
Those 2 things in itself alone would help her manage the gun better because she can put the stock where it needs to be better in the cup of the shoulder. Shooting stance also helps in this area. There are many videos on youtube that covers that if either of you do not know the proper shooting stance when firing a gun. If you stand off balanced or not against the gun (from a lack of better description), you can only expect recoil to do what recoil does without mitigating the effects in other ways.
As Lazy Eyed Sniper has pointed out, there are many who think that the shock absorbing stocks (knoxx) aren't as good as their marketing dept. makes them out to be, but if it works for her, then by all means.
One thing I will add, if she is recoil sensitive, I only have 1 word for you.
LIMBSAVER.
Especially if you need to exchange the stock for a youth stock so it is shorter, do her a favor and add the limbsaver pad while you're at it.
Oh, and I guess I have a few other important words.
LOW RECOIL BLUE HULL HORNADY 00 BUCK for home defense and those cheap low brass skeet shells for practice. You can thank me later.