As the child grows, some problems are replaced by others. One of the most common causes of sleep disorders in children aged 3 to 6 years are night fears and nightmares. All children see nightmares without exception, but in no way do they always become regular and cause discomfort in children's sleep.

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Very often, adults themselves become the involuntary culprits of night fears. Excessive time watching cartoons for children, which in our time are often quite aggressive, adult television shows and movies that contain violent scenes. Sometimes, it seems to adults that the child is playing and does not pay attention to what happens on the screen.
However, the child's brain is designed so that the baby can do several things at once. And this means that at a time when you think the child is passionate about the game, his mind clearly captures everything that happens on the screen. But the child still cannot interpret what he saw and heard correctly, so he interprets everything in his own way.

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In the event that the baby wakes up from a nightmare every night, cry and then cannot sleep for a long time, parents should be careful. Such nightmares are a fairly serious problem, often the result of psychological stress or the presence of a chronic hidden disease in a child.
Many parents do not pay attention to children's fear of darkness and nightmares, considering them something completely frivolous. Sometimes, you can even listen to advice that they are "whims" in no case should they be encouraged, but should be stopped at the root. This is a very dangerous misconception.
Does my child need treatment?

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Probably not. Most children "overcome" night fears and wake up with a confused awareness, but this can take 1 to 2 years.
If such episodes occur very frequently or lead to other problems, consult a doctor. He can advise you on certain medications or "wake up on time", when at a certain time (15 minutes before the usual wake up with fear or confusion) you wake up the child every night for several minutes.
If your child falls asleep or has trouble sleeping, it will be helpful.

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- Put him to sleep in the afternoon and wake him up in the morning at the same time (both Monday through Friday and on the weekend),
- Do a certain ritual before bedtime,
- Do the last hour before bedtime "quiet time", that is, avoid active games one hour before bedtime.
- Show the child that there are no monsters, etc. under the bed and in the closet, etc.
- Discuss with him before bedtime his dreams of tomorrow,
- Create silence and darkness in the room where the child falls asleep; If a child is afraid of falling asleep without light, then leave him alone with a dim night light,
- Leave the door of the child's room open,
- Remove the television from the children's room, do not show horror movies and programs.
Ignoring children's fears can lead to the development of severe psychosis and nervous breakdowns, for which treatment it will be necessary to resort to potent drugs.
Source for information:
https://www.vix.com/es/imj/familia/5728/que-son-los-terrores-nocturnos-infantiles
https://www.conmishijos.com/salud/enfermedades/trastornos-del-sueno-en-los-ninos/
https://www.dietistasnutricionistas.es/la-alimentacion-influye-en-la-calidad-del-sueno/