Febrile convulsions are a kind of fever fits. It happens in some babies when there is sudden rise in body temperature. Usually a baby fever temperature is between 37.5 - 38.5 degree celcius. However if there is a sharp rise sometimes babies can get these convulsions. Parents should not be too much worried as these are not epileptic. You must lie down your baby is side recovery position give iburofen like Nurofen and call the doctor.