As far as I know, fainting or syncope which is the medical term can occur at any age. The age distribution of syncope shows two distinct extremities occurring more often in teenagers (median age of onset: 18 years) and in people 70 years of age or older. Although the mechanism of syncope remains unexplained in about 40% of episodes, usually the cause of syncope can be determined with great accuracy from a careful history and physical examination. If there is a family history of sudden cardiac death, recurrent syncope might suggest a hereditary problem. Since in your case, your mom and you suffered from fainting bouts, a hereditary connection cannot be ruled out. I would strongly recommend you consult a specialist , neurosurgeon maybe to get a more concrete long term advice. I know of my friend who frequently seeks e-consultation at www.mediangels.com From what I hear, they seem to be pretty good and reliable.