Many other parents and perhaps also you have seen this happen: smiles and laughter while your Baby is sleeping.
So: Why do newborns smile in their sleep? Or even laugh?

Maybe you have seen it when you watched your Baby sleep. Or Maybe you could even hear it from another room when your little one was laughing while you actually put him to sleep a little while ago. Then you check and you find out he is still there with his eyes closed. Still…sleeping?

During the first months of their lives, when Babies smile and laugh while they are sleeping, it is without any emotional content behind it. Those actions are only a subcortical response from their brains, which happen most likely when the baby is drowsy or during REM stages of sleep.

Smiles and Laughter as a social and emotional gesture, are usually recognized and learned around month 3 to 4 of a baby’s life. For further reading on this, when babies have their first laughs, and what you can do to help them to get there, see this article from our website.

Following, I will tell you in depth what I found out about smiles, laughs and other noises a baby does, while it is actually asleep. So you know what is normal and what is not, and when to worry or relax.

If you want to make it easier for your little one to enter sleep-mode, read here about the number one trick to put babies to sleep.

You want to have a good laugh with you baby together? Check out our funny baby onesies shop:

What Does ‘REM’mean?

So what exactly is this ‘REM’ stage or phase, when it can happen that a baby smiles, laughs or – as I will mention later in this article – even jerks, whimpers, cries or jumps?

All humans – no matter if infants or adults – have two stages of sleep. The previously mentioned REM (rapid eye movement) stage and the non-REM stage.
The interesting thing is that those two stages are very different.

Non-REM Stage

The non-REM stage is the first thing that happens to us when we actually start to fall asleep. If you want to analyze it in detail, there are 3 different stages within this phase of non-REM sleep.

• 1. Phase is when you just closed your eyes and you slowly slide into dreamland. But is easy for you to wake up by a noise or another external action.
• 2. Phase means, that your heart rate slows and also your body temperature drops a little bit. Everything is getting ready for deep sleep.
• 3. Phase = deep sleep. It won’t be as easy to wake you up because your body is kind of in standby mode. If someone or something is waking you up in this stage though, you will feel maybe confused, disoriented or even a bit dizzy for a little while.
  In this very important deepest phase of the non-REM stage, your body will repair and regrow tissues, build bones and muscles and also strengthens the immune system (and our mum always told us, not enough sleep will make us sick…another thing that she was always right with, haha).

This whole process of non-REM sleep can last up to 90 minutes.

REM Stage

The REM stage is what comes after the non-REM stage. Here we have a more restless sleep, our eyes move and we actually dream.
Those REM stages are a lot shorter than the non-REM ones, but they become longer as the night goes on. They can end up being as long as 60min in the last stages of our sleep.
After a REM stage, the non-REM stage starts all over again. These sleep circles repeat themselves a few times overnight until the body has enough rest and we wake up.

I will talk about these REM and non-REM stages later on in this article and explain, why they are important to answer the question ‘why do newborns smile in their sleep?’ in more detail.

Why Do Newborns Smile In Their Sleep? – Other Explanations

There are also some additional theories to the answer you read above, as well as an old believe that just turned out to be wrong and even a religious explanation.

Safety Purposes?

Some experts are convinced that these smiles are a part of a series of natural reflexes, to make the newborns more appealing, cute and loveable. This will prevent them from becoming abandoned and keep them safe. This goes along with some other characteristics of babies like big eyes for example, that just activate instincts in us to take care of them.

Smiles Because Of A Happy Dream?

Of course, the first thing that freshly baked parents think when they see their new family members smile in their sleep is, that they dream something nice, or relive a happy or funny situation. But as stated above, babies only learn about smiling and laughing as an expression of joy later on in their lives around month 3 to 4 or even later than that (here is the article to this topic again). It differs from baby to baby.

Smile because of passing gas?

Another popular belief is that Toddler smile when they pass gas in their sleep. But there is no evidence nor scientific research on that. So it is kind of an urban legend, probably starting with a mom or a dad who witnessed both incidents at the same time and decided that there has to be a connection. But after some research on that, it seems like there is no truth behind that.

However, it is true that if your baby is uncomfortable in bed and maybe wakes up crying, a reason for that could be that there are some gas bubbles somewhere in his system and some belly rubs can help to release that gas to one way or another.

When Babies Smile In Their Sleep Do They See Angels?

Even though there are scientific researches on the question ‘why do newborns smile in their sleep?’, which came to the results I mentioned before, there is also one believe that has a religious answer to this phenomenon.
For generations, some people believe that babies can see angels and that they even talk and play with them in their dreams. Also nowadays the internet is full of people who are convinced that this is actually what is going on and that this is the reason, why babies smile or even laugh while sleeping. Angels make them happy.

It is a nice thought and worth mentioning here. I guess you have to decide for yourself which explanation sounds better to you or makes more sense and is plausible.

What Else Can Be Unusual When Your Baby Is Sleeping?

So we covered the question why do babies laugh while sleeping. But during my research to find an answer to this, I stumbled upon a few more unusual things that parents sometimes observe when they watch their sleeping toddlers. So what is the matter with those?

Newborn Twitching While Sleeping?

You maybe see your baby jerking or twitching in its sleep. Sometimes it can even seem like they are trying to jump while being in dreamland and laying down in their little baby beds.

Those actions are also completely normal. The development of the nervous system in the first weeks of a baby’s life is the cause for those movements. It happens during the REM stage of the sleep, which is explained earlier in this article.
In this phase, the newborn activates circuits throughout the developing brain and it subconsciously learns about his limbs and how he can move them. And this can result in movement and therefore in twitching, jerking or even jumping while a baby is actually sleeping.

What Do Infants Dream About?

The interesting discovery here is, that while adults only spend about 20% of their sleeping time in a REM-phase, this percentage is significantly higher for infants. They spend more than 50% of their sleep in this phase. Which means, that they actually have a lot more time than we do, to have a dream.

So the circumstances are given. Now there is just the question: What do infants dream about?

No Differences?

Of course, this is hard to find out, since no one can actually know what really happens inside a babies head when they are sleeping. They also can not tell us what happened in their sleep due to the lack of communication skills of course.
However, after numerous studies about this topic, some experts are convinced that babies dream just like we do. Dreaming is the main characteristic for the REM-phase, so why should this be different for babies?

…Or Maybe It Is Different?

On the other hand, there are skeptics who question the ability of babies, to have a solid dream like we adults do.
Our dreams are made up of past time events, experiences, interactions, dialogs, different settings, storylines, a sense of ourselves and people that we know or that we make up in our minds.
Those experts simply point out, that a newborn won’t have the necessary mental skills yet, to make up complex things like dreams.

For example, one of the skills a baby has to learn over time is to have a sense and idea of themselves, other people and even objects. So before they do that and actually interact with other things and people via language, a sense of themselves, etc, would they even be able to have an imaginary construct like a dream?

Another point that those experts stress is, that babies are going through a phase of incredibly fast learning processes during the first years of their lives. A vast amount of growth and development happens during sleeping.
So the conclusion here is, that a baby’s brain uses those REM-phases to develop new neural pathways and is too busy with that, respectively has no more power left, to construct a dream.

Well, as pointed out before it is actually impossible to find the true answer here. Experts have many different approaches to it, but no proofs for their theories.
Babies go through the same sleeping phases, but don’t actually have an enough developed mind to have a dream.
So it is fair to assume that the answer lies somewhere in between and babies have a different form of dreams than we adults do. How those infant dreams look like can only be assumed and speculated.

Can Newborns Have Nightmares?

So, assuming that they do have some form of dreams, can newborns have nightmares, too? We all know that people (and animals too) not always just have nice and sweet dreams. Sometimes we dream obscure, weird or even frightening dreams. This leads me to this next question here: ‘Do newborns have nightmares?‘.

It is an often asked question throughout many different internet forums. The reason is, that some infants seem to have some weird experiences and seem to have some bad scenes during their sleep. They can whimper, whine or even cry, while not actually being awake.

If you experienced the same with your toddler and you are concerned, don’t worry. It is a normal occurrence and as mentioned before, it is something that many parents went through before.

Again, it can just be speculated why that happens and even though scientists put different theories out there what happens in a baby’s sleep, nothing can be proven.

Should You Wake Your Baby?

The thing that you should know is, that you should not wake up the baby when it is still sleeping and just makes some sounds in his or her sleep. If it really has a problem and for example feels uncomfortable, it will wake up and let you know with what babies always do when something is not right for them: they will cry. But if your little one is making just some weird noises in his sleep, you shouldn’t wake him up straight away. Mostly, those noises will stop after a little while.

The reason behind this is, that if you repeatedly wake them up because of the smallest noise they make, and try to bring the baby back to a more comfortable sleep, it could make the toddler be unable to fall back to sleep without you in the future.

So it’s best to accept some noises during sleep time and don’t always think your baby has a hard time because of some whimpering sounds. Just like the smiling and laughing which I talked about earlier on, those actions sometimes don’t have the meaning that we give to them.
When your baby wakes up and is crying, it is time of course for you to be there and figure out, what the little one needs and what you can do for him to make him feel better. Maybe it is because of gas, or maybe they feel too cold or warm.

Night Terrors

Another phenomenon which should be mentioned here are the so-called ‘Night Terrors”. A small child can seem to be awake, scream, cry and what not, but actually and just like with the whimpering during sleep, it is not really conscious of those actions and has forgotten about them in the morning.

They should be treated differently, as the children could actually hurt themselves during a night terror, as they seem to be almost like a sleepwalker.

But first of all, they only occur in about 3-6% of all children. So it is most likely that you won’t have to deal with that.

Second of all, this phenomena is only common for much older children. Even though some cases have been reported where the child is just about 18 months old, this phenomenon is usually found in kids between the ages of 4 to 12.

Because of those reasons, this article excludes the treatment possibilities for this problem and should be the topic for another article. But if you ever have to deal with it, one treatment could be that you wake up your child 10 minutes before the night terrors usually occur and thus just skip them.

Closing Words

Why do newborns smile in their sleep?

We hope that this article was informative for you and that it answers this question.

If you made it to this part of the article, thank you and please check out the heart of this website: our shop where you can find the funniest baby Onesies, as well as other funny and useful things for your new family member!

Also, to let you finish this article with a smile, here is a topic related video of babies laughing during their sleep. It will make your day ;).