In the midst of age-old stereotypes of horrible mother-in-laws, are there any in tradition that are portrayed in a more favorable light?
Why yes, there are.
Lakshmi and the doll
A folktale from India, in which a young woman lives alone with her mother-in-law, whom she loves very much, in the absence of her husband. When the mother-in-law passes away, she makes sure to leave young Lakshmi with a doll that takes on her role of encouragement and advice.
(Read the story in this book)
In this Hindu story a mother-in-law goes out of her way to trick a lazy daughter-in-law into observing a holiday in the proper manner - but she does it with caring and work, instead of scolding or bullying.
(Read about it in this book)
The farting girl
In this hilarious Japanese folktale, a girl marries into a family in a distant village, and she is so scared she'd be judged that she holds her fart for weeks (have you ever tried to hold a fart at your in-laws' house?). When her mother-in-law notices that she is getting sick, she coaxes the truth out of her, and then encourages her to fart away. "We are all family now." The husband is not so kind, and she tries to return the wife to her family, even though the mother-in-law begs him not to. But all is well in the end.
(Read the story here)
Petrus Alfonsi' medieval collection of anecdotes includes a story about a mother-in-law who helps her daughter-in-law get away with having a lover - when the husband comes home unexpectedly, the two women spread out a large sheet to "show him," while the lover escapes behind it...
(Read the story in this book; read an article about these stories here)
The cheerful prince
This Hungarian folktale collected from Pályuk Anna is essentially a version of Rumpelstiltskin, but one that involves a much kinder prince, as well as a kind mother-in-law. When someone claims a girl can spin straw into gold, the entire royal family bands together to help her succeed at her task.
(Once again, there is no English text - or Hungarian, I found this one in the archives. But! It will be included in my upcoming folktale collection ;) )
Any other mother-in-law stories I should include on this list? Let me know!