If the cause of kidney stones for a person is low potassium, she can drink juice made from peeled apples regularly and have an optimum potassium level.
Having a good potassium level prevents kidney, bladder, and gallbladder stones.
No, hers were calcium and oxalate. She went on a diet for it, wife and I did the same insmypathy for her - I lost 40# in less than 2 months on that diet.