Why do babies sleep with their butt in the air

Why Do Babies Sleep With Their Butts in the Air? And Other Curious Sleeping Positions Explained.

As any mom knows, babies seem to take delight in getting into the most bizarre and seemingly uncomfortable positions!

It’s often hard to understand why they do what they do but most of the time it’s completely normal and nothing to worry about!

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I’ll explore several of the possible reasons why they insist on sleeping with their tush up and other wild baby sleep positions!

These theories are plausible from a scientific point of view, but no one has been able to prove them directly.

baby sleeping

Why Do Babies Sleep With Their Butt In The Air?


Sleeping like a baby? More like sleeping like a contortionist! From tiny tots to fully grown adults, we all do the sleepy shuffle before finally drifting off for the night.

And did you know, once they hit 6 months old, babies become masterclass movers as they learn how to use their new muscles.


It turns out, they’re just trying to recreate that cozy feeling they had in their mama’s womb. Who can blame them for wanting to relive the good old days, right?

But wait, there’s more! Some doctors believe that babies actually have muscle memory and their little bodies remember the positions they were in before birth. So when they curl up with their booties in the air, they feel safe and snuggly just like they did in the womb.

So next time you see a baby napping booty-up, you’ll know that they’re just taking a trip down memory lane. Sweet dreams, little ones!

Crawling is Around the Corner

It is common to see your babies assuming that position when they are about to start crawling. In most babies, crawling starts by getting on the knees consistently, and once they are comfortable with this position it’s off to the races! 

Cuddly Feels

Sleeping on the knees give baby a similar feeling they get when they are being held or cuddled up by their parents. 

Why do babies sleep with their butts in the air? Baby sleeping with bum in the air

Common Bums in the Air Myths

There are a lot of untrue pieces of information flying around! Some are a result of traditions; some are a result of misinformation. Today, we will debunk these baby sticking bums in the air myths.

  • Babies that stick their butts in the air need siblings – Some parts of the world have a cultural belief that when babies stick their butts in the air, they want siblings. This may sound cute and all, but it cannot be proven in any way.
  • Overfed babies stick their butts in the air – Another popular myth about why toddlers stick their butts in the air is that they have been overfed. Some believe that when a baby eats too much, they become uncomfortable and assume that position to ease the pain. This also cannot be proven. A baby would most likely cry when they feel uncomfortable from overfeeding. 
  • A baby will develop complications from sticking their butts in the air – Some think that whenever a baby sleeps with their butts stuck in the air, they are endangering their chest. This is only half true. If they did this forever it could lead to troubles but babies naturally revert to sleeping on their backs after a while of sticking their butts in the air.
  • A baby gets weak knees for sticking their bums in the air – A baby sleeping on their knees is actually a sign that their muscles and skeleton are developing right on schedule. It takes muscles to move those legs, right?!
baby sleeping with knees under

Bum In The Air Facts

After years of observation, here are the facts about why babies sleep with their bums in the air;

  • It is a sign that your baby is ready to crawl or has started crawling.
  • Sleeping with bums in the air is not an abnormal thing. Most babies do it
  • It is a sign that your baby has developed skeletal strength since they can kneel, unlike before.
  • It is very comfortable for your baby, and this comfort is due to muscle memory. It is a baby’s way of re-enacting the comforting scene they experienced in the womb.
  • Most babies revert to sleeping on their backs after a while of sleeping with their bums in the air. For these babies, it poses no threat whatsoever.
  • Due to one complication or the other, some babies never revert to sleeping on their backs. Sleeping with their bums in the air may pose a significant threat to these babies. They stand a risk of respiratory complications and sudden infant death syndrome.

Other Baby Sleep Positions

Another baby contortion that may amuse you is when you see a baby that sleeps with its legs up (though not for long). Funny right?

That does not seem remotely comfortable, no matter how you look at it. The only plausible explanation for this behavior is the temporary comfort that the sleeping position offers these babies. The same reason you roll all over the place

Similar to this are kids who jerk their legs between intervals when sleeping. This is more explicable. It shows growth when babies jerk their feet up while sleeping and slam them against the bed.

It is called Moro-reflex, and it is a sign of developing motor skills in babies. It is quite common in babies that are 3 months and older.

Finally, as a parent, if you discover that your baby sleeps with their legs up, you should check the baby for any sign of discomfort. Try swaddling the baby a little and adjusting its sleeping position until you think it would be comfortable.

Baby sleeping in Frog position

baby sleeping in frog position

Babies sleep like frogs for the same reason why they sleep with their butts in the air. Whatever sleeping posture the baby assumes is a matter of comfort and how much that posture looks like what they want to recreate.

Essentially, it could be due to comfort, muscle memory, and skeletal muscle development in babies older than 4 months.

Whether your baby sleeps like a frog or shoots their butts in the air, take it that it is the most comfortable position for them.

In babies less than 3 months of age, the only logical reason is that the baby’s muscles and bones are not yet grown and stretched out. As your baby grows, their sleeping position is bound to loosen up.

Should you be worried about this? Not! Sooner or later, your baby would finally revert to sleeping on its back. However, if you notice difficulty over time, you could help your baby by swaddling them or rocking them to sleep. After all, the bottom line is comfort.

Why Do Toddlers Sleep on Their Knees?

Toddler sleeping with bum in the air

Sleeping on the knees is no different from when a baby sleeps with their butts in the air. They are just trying to get comfortable!

Like all the other similar sleeping positions, don’t worry too much about this, except if your baby has difficulty reverting to sleeping on their back.

Why Do Babies Sleep With Their Legs Open?

Baby sleeping with legs spread

When a baby sleeps with their legs open, it could be due to either of the following reasons;

  • The baby is tired. In this case, that sleeping position is only temporary, and the baby is bound to shift as they go deeper into sleep.
  • The baby feels more comfortable. Just like in the case of sleeping like a frog, some babies find it more comfortable sleeping with their legs open.
  • The baby has a lesser muscle tone. These babies have lesser muscle resistance when their bodies are at rest. Therefore, they are more comfortable sleeping with their legs spread by default.

Finally, depending on how long you observe this in your baby, you may have to step in for corrections. However, it is usually nothing to bother you about in most cases.


Babies sleep in any number of seemingly uncomfortable (for us adults) positions. And this is perfectly normal!

Whether bums in the air, legs in the air, or like a frog it’s all part of the process of your baby getting comfortable in their new skin.

Do you have any funny stories of your babies contorted sleep? 

Why do babies sleep with their butt in the air?

Why do babies sleep with their butt in the air

The most common reason babies sleep with their butt in the air is in an effort to get more comfortable. This could also be because it’s a similar position to how they slept in the womb or a sign that they are growing some new baby muscles.