My 11 month old grandaughter fell asleep, while she was sleeping, she spiked a fever.woke her up, gave her Tylenol, about 5minutes later, she had a seizure, she stopped breathing&her eyes rolled back, lasted about 3-5 minutes. She just learned to walk, but, I noticed she started falling constantly, mostly hitting the back of her head lots of times.What wud cause a seizure...is this serious condition? Im so worried.