To address this concern, you’re a parent and you didn’t freak out, right? Lol.
I used to be a purser for a major airline. I am amazed to think now how calm and collected I could be when there were issues on board. We had medical emergencies, severe turbulence, unruly passengers, and even a pilot lighting a match in the toilet to, um, cover up his business (yes, that really happened and the bathroom smoke detector went off.) People trying to join the Mile High club were always fun to deal with. Running out of meal choices and and sweetly offering the only available option taught me excellent diplomacy skills. Fun times!
I learned so much from that job: how to handle large groups of people, how to delegate, how to communicate with authorities (pilots) and passengers, how to keep calm in both alarming situations and annoying ones, and on and on. There was so much more to the job than just serving food and opening the emergency exit. The same will be true for an RA.
Anyway, I think there are a lot of pros to being an RA and not too many cons. Not enough to make it not worth doing. She’s an adult and should do it if she wants to.