My 4year old is having seizures why?

Internet Medicine. Wow. I am very sorry, but there is no way this answer can come from the internet. If your child is having seizures they must be in the er urgently. Then the doctors in person will search for the reason and hopefully find a way to treat and cure the cause of the seizures. If your child is not at the hospital yet, please call 911.
Get help now. Can be from multiple causes, some life threatening. Get to pediatrician or er now!