Hi Patricia,   Yes, there are hereditary forms of aneurysms.  And note that many different organs in the body can get them.  Two of the most common affected are the brain and aorta.   An aneurysm is an out-pocketing or dilatation of blood vessel in your body.  In older people, uncontrolled high blood pressure is usually the cause of the dilatation. Aneurysms are concerning because dilation of a vessel causes the wall to thin and become less elastic.  These changes put the vessel at much greater risk of rupturing.  For aortic aneurysm, different types diseases that affect structural proteins in cells, like Marfan's syndrome and Ehrler-Danlos syndrome, do predispose people to this condition.  In the brain, aneurysms occur also as a result of high blood pressure and hereditary factors.     Brain aneurysms cause symptoms much like your daughters, though they are significantly less common in young people.   However, if she has not been to the doctor's, she should go soon to find the cause of her symptoms - and yes, a CT scan or MRI of the brain is probably warranted.  And if the symptoms increase suddenly, she should go the emergency room immediately.   Hope this helps.   To you and your daughter's health, Neil MD