Hi Merrym, I just saw your posting & thought I would give you this website to visit: www.dizzy.com. It is the American Institute of Balance, and has a wealth of information. I have suffered from vertigo, and call it the "illusion of movement". If it is true vertigo, it can disappear as quick as it came. Maybe it will last only a few days, a few hours, or less. Did she have a recent blow to the head? Tell your dr if she did. Symptoms are brought on by head movements, and are most prevalent when you wake up and go from laying down to sitting up. That is usually when the room starts spinning around you and you get that feeling of nausea. The cause is from the inner ear, as you may know. There is no 'fix' but you can try Gingko Biloba, a herbal supplement, it may help ease the symptoms. Hopefully it is vertigo and nothing else.
Hope this helps, good luck.