Looking for guidance for my ten year old daughter

Approximately 6 months ago, my daughter Cayleigh started complaining of severe migraines and a sore neck up to 4 to 5x a week. We had her vision checked, normal. We visited our physician, they saw nothing out of the ordinary, was told to give ibuprofen. Approximately one month ago, Cayleigh was visiting a friend when she had a grand mal seizure. The squad was called, and she had her very first ambulance ride. Hospital did CT scan, came back normal, referred us to neurologist at Dayton Children's. Neurologist ordered EEG, which was stopped after 30 minutes, because Cayleigh had already had 7+ absence seizures. He sent us home with Keppra 500 mg 2x daily, and a versed nasal injection. He ordered MRI. MRI results came today via phone, and I tried to comprehend everything the nurse was saying and write it down. But she said the MRI showed Chiari malformation 3mm below opening. She expressed this is nothing for me to be concerned about, but with Cayleigh's symptoms, and all of a sudden seizures, I am extremely concerned. Cayleigh has always been healthy, has never seen a hospital until this past month. Never any signs of epilepsy, until her first seizure a month ago.

Thanks everyone! I appreciate all the help and encouraging words. Reading all the information now.