A friend asked for an expert’s help in understanding night terrors in kids, what causes them, and what to do when they happen. Here’s what Dr. Julie Yeh, a pediatrician at Greater Baltimore Medical Center, wrote back when I asked for guidance:

"Night terrors are a common form of sleep disturbance that occurs during non-REM sleep in young children, usually between the ages of 2 and 6. Typically, the child will wake up very frightened and upset during the early part of the night - somewhere around one to four hours after falling asleep.

"Symptoms include screaming, crying, and sweating with a rapid heart rate. Often, parents are unable to wake the child up and the child will not have memory of the event in the morning.

"These episodes can last anywhere from 5 to 30 minutes and can be distressing for parents, as the child is often inconsolable. (The parents) should offer comfort, safety and reassurance to their child knowing that he or she will come out of it on their own. Yeh says that though it’s natural for parents to want to wake children up while they’re having a night terror, it’s exactly what they shouldn’t try to do. "If night terrors occur on a regular basis, there may be some benefit to waking the child up before the time that he usually has one," she writes. "This may interrupt the sleep cycle and prevent the night terror."

What else can be done to prevent night terrors? "Night terrors can be exacerbated by sleep deprivation or poor bedtime routine, so it is important that children get enough rest and go to bed at the same time every night," Yeh writes. "Most children eventually outgrow night terrors, and medication is rarely necessary."