In southern India, a tale is told of a kindly Brahmin who had a good mother, but his wife and mother-in-law were jealous and mean, mistreating her and treating her like a slave. The poor woman was too elderly and feeble to defend herself.
The unfortunate mother fled one night to the shrine of the village goddess and prayed to her. The goddess answered and gifted her with a magic mango. Returning to her home, she partook of the fruit, and felt her skin grow firm and youthful once more. She rose from her elderly stoop as her body grew strong and young again. Now she could defend herself and no longer had to endure the humiliation at the hands of her son's wife.
The Brahmin's wife was furious, and sent her own mother to the same shrine with a fabricated tale of woe. The goddess, of course, wasn't fooled, but gave her a fruit all the same. Returning to the house, the mother-in-law eagerly bit into the fruit. At first, as strength flowed into her body, she was delighted and thought all was well, but then grey-brown fur began to sprout from her body, and her hands and feet transformed into an ass's hooves. Falling to all fours, she tried to complain, but only a donkey's bray emerged, as she was wholly changed into an ass.
This tale is why in India today, if a person declines steadily in social standing or achievement, there is a proverb, "Little by little, the mother-in-law became an ass."