Parasomnias in children: night terrors, nightmares, sleepwalking

Three phenomena that are easy to mix up

Night terrors, nightmares, and sleepwalking differ mainly in when they happen during the night and in what the child remembers the next day. Night terrors and sleepwalking tend to occur in the first half of the night, nightmares in the second.

A night terror happens during deep sleep, usually in the first two to three hours of the night: the child screams, sweats, and sometimes has their eyes wide open, but doesn't recognize their parents and stays inconsolable throughout the episode. It isn't a real awakening, the child stays largely unreachable, and the episode is gone from their memory by the next morning.

A nightmare, on the other hand, happens during REM sleep, more often in the second half of the night. The child wakes up for real, recognizes their surroundings, actively seeks comfort, and often keeps a precise memory of the dream, sometimes for several days.

Sleepwalking shares the same deep sleep as night terrors, and the two sometimes coexist in the same child. The child gets up, walks, sometimes talks, eyes open without really being present, then goes back to bed without remembering any of it.

Frequency and age: very common, rarely a cause for concern

Night terrors affect more than one child in two at some point in childhood, peaking around 18 months before gradually declining. Sleepwalking follows a different timeline: it sets in later and peaks around age 10, before fading during the teenage years. According to a family-medicine review, only about 4% of parasomnias persist beyond adolescence.

Both also run in families. In the Quebec study cited below, sleepwalking affected 22.5% of children with no parental history, 47.4% of those with one sleepwalking parent, and 61.5% of those whose parents had both been sleepwalkers. Up to a third of children who had early night terrors went on to develop sleepwalking, which suggests the two are manifestations of the same underlying mechanism. Heredity is one factor among others, and it simply explains why some families are more prone to it than others.

What should you do during a night terror or a sleepwalking episode?

During a night terror or a sleepwalking episode, the most useful thing is to stay near the child and keep them safe. Waking them or trying to reason with them doesn't help: they aren't really reachable, even with their eyes wide open. Speaking in a calm voice without expecting a response, and making sure they don't bump into anything, is usually enough. The episode rarely lasts more than a few minutes and ends with a spontaneous return to deep sleep.

Picture a typical scene around 9:45 p.m., about an hour after bedtime. A four-year-old sits up in bed screaming, eyes wide open. Their parent sits down next to them, repeats in a steady voice that they're there, moves aside anything the child could bump into, and waits. A few minutes later, the child lies back down and falls asleep again. The next morning, they remember nothing.

Sleepwalking mainly calls for securing the room and its access rather than acting directly on the child: a closed door, a gate at the top of the stairs, a clear floor. Gently guiding them back to bed, without forcing them to respond, generally works better than waking them fully, which can disorient them further. For most parasomnias, the family-medicine review mentioned above concludes that the best management is to reassure the parents and make the environment safe.

Facing a nightmare, the opposite response

Unlike a night terror, a nightmare leaves the child awake and actively seeking comfort. Taking it seriously, reminding them it was a dream, and staying a few minutes is usually enough for them to fall back asleep. A single nightmare doesn't call for any special adjustment at bedtime.

Repeated nightmares around the same theme, though, are worth a closer look: they sometimes follow a recent event (a scare, a change, a story or an image too intense for their age) that can be worth identifying so it can be avoided on the following evenings. An expert consensus paper on chronic nightmares, which isn't specific to children, also cites hyperarousal, traumatic or difficult experiences early in life, and possibly disrupted breathing during sleep.

When should you see a doctor about night terrors or sleepwalking?

A doctor's visit is warranted when episodes become very frequent, when they put the child in danger, or when they suddenly appear in an older child who never had them before. The large majority of night terrors, nightmares, and sleepwalking episodes resolve on their own with age.

Loud breathing, noticeable snoring, or breathing pauses during sleep are also worth mentioning: sleep broken up by apnea episodes can make this kind of episode more likely. Built-up fatigue, a fever, or a sudden change in routine can sometimes be enough on their own to trigger a one-off episode, without signaling a lasting problem.

A few benchmarks help with the decision. A one-off episode after a busy day or a short night: make the room safe and keep an eye on it. Episodes several times a week: book an appointment. In every case, noting the time, the length, and what the child does helps the doctor. Many parasomnias can be recognized from the description alone, but some call for a sleep study, and the doctor sometimes has to tell a parasomnia apart from a nighttime seizure.

Teeth grinding at night, another common feature of children's sleep, is covered in the guide on bruxism.