Maybe start her with a 410/22. It’s like having 2 single shots of different cartridges.
BTW, I started my 10 y/o grandson with a 2x bbl Stoeger in 20ga. He never had a problem. Gave it to his mom when he grew out of it. His mom isn’t very big.
You just took me back in time, lol. The first shotgun I ever fired was a double barrel 20 ga of my grandpa's. Must have been over 50 years ago. Dang, how did all those years fly by when I wasn't looking?