"Night terrors" are a kind of scary dream that occur during deep sleep (usually between 1 a.m. and 3 a.m.). A child having a night terror will often wake up screaming, sweating and breathing fast. The child's eye pupils (the black center of the eye) may appear larger than normal due to sympaticus stimulation. Or, a child may still be asleep when experiencing night terror, with open eyes. In these cases, children will be confused and might not answer when parents ask what's wrong or a child may be difficult to wake. When the child wakes up, s/he usually won't remember what happened.
Nightmares and night terrors in children are usually not caused by mental or physical illness. Often nightmares happen after a stressful physical or emotional event. Night terrors require that parents protect their child during sleep. The home should be safe (use toddler gates on staircases and don't use bunk beds for children who have nightmares or night terrors often). Night terrors usually become rarer and vanish completely when children get older. Talk with your doctor if your child ever gets hurt while sleeping or become unable to function during the day. Your doctor may want to study your child during sleep to exclude epilepsy.