She will practice with 38s, but why do you discourage the 357 mags for defensive loads?
The recoil with the "standard real 357" loads will be truly horrific in an LCR357. I'm talking about pushing 125s at 1,450fps or so, as the Remington 125gr classic semi-jacketed hollowpoints run, or the basically similar 125gr Cor-Bon full-house loads. These are a bit under 600ft/lbs energy out of a 4" barrel. They'll be a bit slower in a 2"...but still an E-ticket ride to shoot.
The "real original class" 357 loads can push a 125 at 1,600fps or more, for nearly 800ft/lbs energy. DO NOT try that stuff in an LCR357, it'll feel like slamming your hand in a car door. Buffalo Bore, Doubletap and now Underwood are selling this class of power in factory ammo.
There are some good milder 357s that are worth looking at: Cor-Bon's 125gr "DPX" is rated at 1,250fps from a 4". Doesn't sound like a big difference but it is. Speer's 135gr "357 short barrel" is the mildest "357" ammo I know of...you'll get ballistics out of a 2" that are similar to shooting the 38+P variant out of a 5" or 6". Nothing wrong with that, and the accuracy tends to be superb with this load in most guns. Remmie's "Golden Saber" 125 is another mellow 357 worth looking at, and Buffalo Bore has a selection of "Tactical Lite" 357 ammo.