If MIL likes and did well with the SP 101 then I'd stick with it. I have an LCR .357 and would only carry 38 or 38 +P in it, no fun to shoot .357 in it. I'm even thinking about selling/trading the LCR when I can find an SP 101 15707.
You don't want her to be a threat to herself and everyone around her. Have her practice drawing, presenting and squeezing the trigger a few times with it unloaded and determine if she could do it effectively under stress. She might be best served with a nightstand gun she can use if someone comes through the door on her. Anyone can stand in front of the target and get decent results. What's a realistic first shot from cover and followups? Practicing with a shot timer can simulate stress. That beep meaning the threat is real and present. Practice these drills with the gun unloaded and make a realistic decision that won't endanger everyone but an actual threat.I have been a Certified trainer Fed./State? Local level for over 40 yrs and agree with what you say. I worked at SGC for years, a high end Class III range/dealer and I can't tell yoo how many snub guns came in used from people that were like "new", who thought they were cute, easy to handle & carry and when they fired them, OMG! That was it! I own them, several and they kick like a Missouri Mule, period. I do load down, using upside down 148Gr wadcutters, the old "flying ashtray" load, around 650-700 fps. Its Ok, but even a steady diet of those can get old fast, especially at (77) and with little to no experience. Imagine what could happen when this sweet little old lady pulls it out and touches off the firsts round? Nothing good that I can imagine! between recoil, muzzle blast/flash & noise, she will be sensory deprived and lucky to have any idea of what is going on around her.(IMHO)