They may sit up in bed, thrash their arms and legs, and seem terrified. Night terrors are often more upsetting to parents than they are to the children who have them. When parents try to calm their children during night terrors, they often find that their children do not seem to recognize them and do not respond to them. This is because children having night terrors are still asleep. Their eyes may be wide open, but in fact they are asleep.
Parents often confuse night terrors with nightmares, when in fact they are very different.
Night terrors are less common than nightmares. Unlike nightmares, night terrors take place during very deep sleep and generally occur during the first four hours of sleep. Though they are rare, they most often occur around the ages of four and five, and they usually stop around eight years of age. Night terrors are not usually considered to be dangerous or to be a cause for concern. It is not presently known why children have night terrors, but they do tend to run in families.