"It comes on very quickly. One minute, you're ok and the next minute, you have a pounding headache," said Adams.
Kassie's been hospitalized eight times and has missed weeks of school.
"I can't sit during school with a horrible headache," said Adams.
Her doctors diagnosed her with migraine -- a painful, often debilitating headache.
Dr. Nate Bennett, a certified headache medicine subspecialist, says migraines are more common in kids than most of us think. About 10-percent of kids under age 12 have migraines -- compared to about 12-percent of adults and teens.
The biggest difference? A child's migraine may last only 15 or 20 minutes instead of several hours.
"That's one of the reasons why a lot of kids are misdiagnosed," said Dr. Bennett.
Dr. Bennett says parents should take note if their child complains of more than one or two headaches a month or headaches with nausea.
"A child that's in the nurse's office a lot of the time is a red flag because there are things that are bothering them. Kids that have a lot of bellyaches that can be migraine," said Dr. Bennett.
Migraines are genetic. Dr. Bennett says it is crucial for doctors to catch children's migraines early, because if left untreated, they may continue to increase in severity and duration.
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