Hi mary mac,
First, if I may talk about FHM first. Since it is a rare form of Migraine disease, and you seem to have a strong family history of Migraine with aura, it is vital that you be treated by a Migraine specialist - we have list you can see here. Have you read our information on FHM? Hemiplegic Migraine - The Basics. Another interesting article that may be of great value to you and your family is about genetic testing a FHM. Hemiplegic Migraine - Genetic Testing May Be Helpful.
Migraine disease and thyroid disease can often be comorbid conditions, meaning they happen at the same time but are independent of each other. Migraine, Headache, and Thyroid. I hope this answers some questions for you.
Good luck
Nancy