Classic Literature with a Happy Ending?

My mother is trying to get back into classic literature and as I read a lot she asked me for suggestions. She just finished “To Kill a Mockingbird” and was looking for something else “classic” to read.

But with the caveat that it have a “nice ending”

She said she wanted to try The Great Gatsby (which she never read) but I told her it’s not exactly a nice ending.

All of my favorites are either too dark or too depressing. She also didn’t really anything like horror or scifi. (Or I would be suggesting Dracula)

I suggested Pride and Prejudice” which She has already read or “Anne of Green Gables “ but she said she wanted something new.

Aside from Shakespeare, anyone have any ideas?