7th Mar 2021

Why do children experience Nightmares and Night Terrors?

Nightmares and night terrors are some of the most common sleep problems children face, causing them to be sleep deprived and develop sleep anxiety. These sleep problems can be common, but they are not always transient. Contrary to popular belief, children do not ‘grow out of their sleep problems on their own’; and children’s recurrent nightmares and night terrors and associated sleep disruptions, if not dealt with in time, can have long-term effects on sleep habits, social development and behavior, academic function, and overall health, years into adolescence and adulthood.

Furthermore, research has shown that when a child experiences sleep problems, it has a negative impact on the parents and siblings’ physical and mental health due to the resulting sleep deprivation (Durand, 2008; Schroeder & Smith-Boydston, 2017).

While nightmares and night terrors are different by definition and characteristics, they both have causative factors that overlap with each other. With nightmares, a child awakens and can then recall details of the scary dream. He/she can be comforted and soothed.

In contrast, with night terrors, a child is still asleep. He/she may sit up, walk around or talk, all the while being asleep – and will have no recall of anything. Comforting a child experiencing night terrors can be very difficult; in fact quite impossible – because though the child is talking and moving around, he/she is still in sleep mode.


Nightmares are dreams with scary, frightening content, which occur in the REM (Rapid Eye Movement) sleep stage. Nightmares tend to wake us up at night and leave us feeling a profound sense of fear and anxiety. Children have nightmares too – in fact, they are so common that more than 50% of all children between ages 3 and 6 years experience nightmares (Mindell & Owens, 2010).

However unlike adults, who can fall back to sleep after waking up from a scary dream, children continue to stay scared, and are reluctant to go back to sleep. Not until 3-4 years of age will most children have some understanding of the difference between dreams and reality. Children will typically have a full understanding of dreams as being caused by one’s own thought processes only by the age of 8 years.

Night Terrors

Night terrors are seen in the Non-REM (Rapid Eye Movement) sleep and usually in the first 1-3 hours after falling asleep. Arousal from the initial 1-3 hours of deep Non-REM sleep is very difficult for children, who will appear agitated, disoriented and confused – and can include intense crying, screaming, rapid pulse and sweating, a glassy stare, or nonsensical vocalizations and incoherent movement. These events usually end quickly, with the child becoming calm and continuing to sleep, but they can last up to 30-40 minutes.

Night terrors are understandably very distressing for a parent to witness – however, during such an episode, parents are encouraged to try to simply keep their child safe, since any consolation and efforts to awaken their child does not help. Parents are discouraged to discuss the episode in any detail with their child, as this could instead increase their fear of going to sleep.

Causes of Nightmares and Night Terrors

As mentioned above, nightmares and night terrors are characteristically different; however, the factors that cause them are strikingly similar.  In trying to understand why children experience nightmares and night terrors, we shall discuss each of the overlapping causative factors in detail below.

1. Overtiredness

Overtiredness is a state of exhaustion when your toddler hasn't gotten enough sleep - when his body has gone from state of being ready for sleep to ‘alert and active’. The body can no longer cope and activates a stress response, pumping adrenalin and cortisol (hormone that keeps us awake and alert) into the body. This interferes with the normal release of melatonin (hormone that makes us drowsy); causing irritability and hyperactive behavior.

Interestingly, overtiredness causes and is caused by inadequate sleep. It’s a loop that keeps on continuing unless intervention takes place with an aim to improve one’s sleep. Research has shown that overtiredness is one of the principal factors causing toddlers to be prone to sleep disruptions such as nightmares and night terrors (Davey, 2009; Durand, 2008; Schroeder & Smith-Boydston, 2017). In fact, overtiredness is the common denominator in most toddler sleep problems - which is why we have created a comprehensive guide that examines the causes, symptoms and behaviours of overtired toddlers, with helpful tips and strategies on how to settle your overtired toddler to sleep. You can access the guide at this link.

2. Overheating

A well known fact is that high temperatures affect the level of comfort while we sleep, making us restless throughout the night. In infant sleep, we know that overheating is a major SIDs risk – so temperature regulation is crucial in order to maintain sleep safety and comfort for our little ones.

Furthermore, sleep research has shown that overheating can impact not just sleep quality, but dream content as well (Lack et al., 2008). This is because temperature affects the way our brain works – and REM dream sleep stage involves increased brain activity – causing us to experience vivid and scary dreams.

Human body temperature normally varies throughout the day, and is especially low just before the onset of sleep (generally, as we become drowsy, our temperature goes down, reaches its lowest level around the break of dawn, and climbs slightly as morning begins). During REM dream sleep stage, our temperature regulation is poor.

Additionally for children, we must also consider the fact that their little bodies are not yet able to regulate their body temperature in the first place. Overheating can exacerbate this, causing children to experience nightmares and night terrors. This is why their room temperature and the quality of their sleepwear is important to maintain a comfortable sleep temperature; not too hot, nor too cold.

Our range of baby and toddler sleep bags and sleepsuits are perfect for keeping your little one sleeping comfortably all night. Made with 100% certified organic cotton, our sleepbags and sleepsuits don’t contain any polyester or synthetic materials or fillings (sleepwear made of polyester and synthetic fibers can trap heat and cause children to sweat profusely and overheat while asleep), free from pesticides and chemicals, thus allowing optimum safety, comfort and breathability.

In addition, our 4-in-1 365 Sleep Bags come with fully configurable 0.5 and 2.5 TOG sleep bags – simply zip the summer bag over the autumn/spring bag to form a warm winter bag, or zip off to adjust to the room temperature or to suit your baby’s changing needs.

Our X-TEND Sleepsuits come in summer, autumn/spring, and winter weights, and has removable zip off arms which means you can adjust the sleepsuit according to your baby’s sleep temperature. Check out our full range here.

3. Fever

As mentioned above, an increase in body temperature while asleep can make children prone to nightmares and night terrors. In a similar way, fevers cause a rise in body temperature and thus affect the way our brain works while asleep – producing vivid imagery and walking hallucinations.

Additionally, fever takes a toll on the body and the mind – making children more tensed and agitated, and susceptible to any existing fears or anxiety, hence causing nightmares and night terrors. 

Our website has a temperature and clothing guide for all our sleepwear products – so you can dress your child appropriate to the ambient temperature and your baby’s needs. Dress your baby to be comfortable, neither too hot nor too cold. Feel your baby's chest regularly to check his/her temperature. Don’t worry if baby’s hands, face, and feet feel cool - this is normal. If your baby is sweating or has a red face, remove some clothing and/or use a lower tog. This may be necessary if your baby is unwell, in which case you should seek medical attention.

4. Stress and Anxiety

Pediatric sleep research has shown that treatment of sleep problems often results in an improvement in a child’s daytime function, including fewer behavioural-emotional problems and increased academic and social behavior functioning. In fact, sleep problems, when considered in the context of normal physical and cognitive-emotional phenomena that occur at a child’s different developmental stages, has found to be more effective (McNamara, 2008; Schroeder & Smith- Boydston, 2017; Wiggs, 2009), thus providing good empirical evidence that stress and anxiety plays a role in many childhood sleep disruptions, such as nightmares and night terrors.

Stress in children can be caused by a number of different reasons, which can include separation anxiety, nighttime fears, and being afraid of the dark; or daytime anxieties about going to pre-school, fears of being alone; or events such as the birth of a new sibling, death of a family member etc. These can all contribute to stress and anxiety in children, making them more prone to nightmares and night terrors (Coolidge et al., 2009; Kibel et al., 2007; McNamara, 2008; Schroeder & Smith- Boydston, 2017).

Always seek medical advice if you have any concerns about your child’s physical or emotional health. A specialist can recommend a program of help tailored to the individualised needs of your child.

5. Other Illnesses and disorders

Often sleep disorders can involve more complex problems such as those associated with breathing (e.g., apnea) and limb movement problems (e.g., restless legs syndrome); which are also known to make children more prone to nightmares and night terrors. Although uncommon, studies have shown that a number of psychiatric disorders, depression disorders, attention-­ deficit/hyperactivity disorder (ADHD), and autism; as well as physical disorders such as neuromuscular disorder and obesity related to sleep problems in children. Children with asthma, eczema, gastric reflux, bladder issues and bed-wetting problems may also be more prone to sleep disruptions at night.  If you have any concerns regarding these issues causing your child to have sleep disruptions, be sure to consult your family doctor or visit a specialist for medical advice.

6. Developmental Milestones

As children grow and meet their developmental milestones, they learn new skills and their bodies are able to do new things – which can contribute to some degree of anxiety and stress. This is normal and natural, and the child may not even be aware of these thoughts during the day- nevertheless, these can manifest in their dreams. Research  reveals that referrals for nightmares are common for children aged 4-6 years, which increased again during the adolescent years – suggesting their conflicts and struggles with their new found independence and the many new and varied stimuli they receive everyday through social interactions, books, television, the internet, etc (Schroeder & Smith- Boydston, 2017).

Dealing with toddlers sleep issues can be tricky, mainly because toddlerhood is a dynamic stage with several seemingly rapid developmental milestones- it can all seem a bit too much to handle at times. Take it one day at a time, and don’t be too hard on yourself. Soon you’ll be able to figure out your toddler’s unique solutions to going back to sleep after an episode of nightmare or night terror, and progress towards better quality sleep for your toddler and yourself.

If you know someone who may benefit from this article, then please share this article with them.

We wish you and your toddler lots of restful nights’ sleeps!

References List

Coolidge, F. L., Segal, D. L., Coolidge, C. M., Spinath, F. M., & Gottschling, J. (2009). Do nightmares and generalized anxiety disorder in childhood and adolescence have a common genetic origin? Behavior Genetics, 40 (3), 349– 356. /10.1007/s10519-009-9310-z

Davey, M. (2009). Kids that go bump in the night. Australian Family Physician, 38 (5), 290-294.

Durand, V. M. (2008). When Children Don’t Sleep Well: Interventions for Pediatric Sleep Disorders: Therapist Guide. Oxford University Press, Incorporated.

Mindell, J. A., & Owens, J. A. (2010).  A Clinical Guide to Pediatric Sleep: Diagnosis and Management of Sleep Problems (2nd ed.). Philadelphia: Lippincott Williams & Wilkins.

Kibel, M.A., Molteno, C.D., & De Decker, R. (2005). Cot death controversies. South African Medical Journal, 95 (11), 853-857.

Lack, L. C., Gradisar, M., Van Someren, E. J., Wright, H. R., & Lushington, K. (2008). The relationship between insomnia and body temperatures. Sleep Medicine Reviews, 12 (4), 307-317. /10.1016/j.smrv.2008.02.003

McNamara, P. (2008). Nightmares: The science and solution of those frightening visions during sleep. Greenwood Publishing Group, Inc.

Schroeder, C. S., & Smith-Boydston, J. M. (2017).  Assessment and Treatment of Childhood Problems, Third Edition: A Clinician's Guide. Guilford Publications.

Wiggs, L. (2009). Behavioural aspects of children's sleep. Archives of Disease in Childhood, 94 (1), 59. /10.1136/adc.2007.125278

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