11 month old niece

I have an 11 months old niece. So far she had two episodes of what I will describe. The first one she had New Year's eve and the second just had it yesterday. So, this what happens...she gets very hyperactive (more thank usual or normal self), doesn't nap when she you usually does, she does this thing with her eyes where she rolls her eyes counter clockwise and then closes them shut, she also loses control or grab of her head, arms/hands and legs. What I mean by that is her hand has no support and falls downward, if you have her stand she collapses, and her arms are floppy and have no tone/strength to them. After all these happen she falls asleep and when she wakes up she's back to normal self. She was taken to the hospital 2 for this and had the 2 hour eeg and over night eeg. Nothing shows and everything seems normal. Neurology thinks it's seizure, but not 100% sure.  She has an MRI schedule.

Just wondering if anyone has experienced this before and what it could possibly be.