Has she been to her doctor to determine why she has migraines? One big cause for them is food allergies and by simply avoiding certain foods, she can be rid of her migraines. I get migraines from MS. In my case, they are caused by inflammation and usually occur when I have forgotten to take my NSAIDs. Some people get them from weather changes or hormones.
Here is an article on migraines and food intolerance: http://www.betterhealthusa.com/public/339.cfm
My mother had migraines for years until she went to the doctor where she was told to avoid coffee, aged cheeses and wine. She hasn't had a migraine since. My migraines are usually triggered by bright sunlight. But mine usually are MS related so that's a whole different ballgame.
