My cousin is nonverbal Autistic and has been experiencing seizures out of the blue

I just got wind today that my nonverbal autistic cousin (34F) has been rushed to the ER twice recently due to convulsing seizures. She has never had this issue before and I'm just very very worried about her. They put her on anti-seizure medication but that just means they can't run tests to see what the cause is. I just wanted to post this to see if this is something that is common or a cause for concern.