11 Reasons Why Do Babies Cry In Their Sleep

It can be a little unsettling to hear soft whimpers or sudden cries in the middle of the night, especially when your baby doesn't fully wake up. You start to wonder why do babies cry in their sleep. This question often leads to more curiosity, and the answer isn't just one thing. It helps to know what's coming ahead so you can understand what's typical and what might need attention.

Part 1. Why Do Babies Cry In Their Sleep? 11 Common Reasons

There's always a moment of confusion when you hear your baby cry while sleeping, especially when everything else seems calm. Before you try to guess what's behind it, it helps to break down what could really be going on.

1. Sometimes It's Just Baby Noise

You've probably heard the phrase "sleeping like a baby" used to describe a peaceful, silent night. But anyone who's spent a night near a newborn knows that baby sleep is far from quiet. They snort, grunt, whimper, cough, and sometimes cry while staying fast asleep. It doesn't always mean they're upset or uncomfortable.

These sounds are often just part of how their little bodies adjust to each sleep stage. A short burst of noise can sound like crying, but it's usually nothing more than a passing moment. They won't remember it, and you'll probably be the only one losing sleep over it.

2. A Wet or Dirty Diaper

If your baby cries during sleep and nothing else seems off, there's a good chance the diaper needs a check. A wet or dirty diaper can quickly turn into a full-blown fuss, especially during the night. Newborns have sensitive skin, and even a little discomfort can wake them up or cause them to cry without fully waking. Sometimes they don't even need a full change.

A small leak or damp feeling is enough to set them off. If your baby poops during the night and cries, you should change the diaper as soon as possible. You can also try to put your baby to bed in an overnight diaper to lower the chances of that happening.

3. Being Hungry

One of the most common reasons babies cry in their sleep is simple hunger. Newborns grow quickly, and their small stomachs need frequent refills to support those early growth spurts. In many cases, night crying happens because your baby is ready for the next feeding, especially during those first few months.

This usually continues in babies between five and nine months of age, and sometimes even longer. If you plan to night wean, which means gradually reducing or stopping nighttime feedings, it's always best to talk with your pediatrician first. Until then, you should learn your baby's hunger cues and stay a step ahead of feeding time so you can handle those sleepy tears in the moment.

4. Gas Issues

Babies often cry in their sleep because they're gassy, especially after a feed, before you tuck them in. If the gas doesn't come up, it can sit in their stomach and build pressure to release, which causes discomfort when they're lying down.

Some babies also suffer from reflux, and that can make the gas more intense. You might notice they're crying more at night if they're fine during the day, and that usually happens because they're less upright and more still. These small position changes affect how gas moves through their body. When it doesn't pass easily, that pressure can cause your baby to cry during sleep. To ease this, you should gently burp your baby after every feed, and most importantly, do this after the nighttime feeds.

5. Moro Reflex

If you're wondering why your newborn suddenly cries during sleep, it could be the Moro Reflex. This is one of those early developmental milestones where the baby's arms or legs jerk out without any warning. It's completely involuntary and happens because your baby doesn't yet have full control over their tiny body.

That sudden twitch or jolt can interrupt their sleep and cause them to cry, even though they're still mostly asleep. It usually shows up more in the first couple of months and gradually fades away as your baby grows. You might not be able to stop it entirely, but swaddling your baby before sleep can help you limit those sudden movements.

6. Getting Too Warm or Too Cold

Another reason your baby might cry during sleep is that they're either too warm or too cold. You should try to keep your baby comfortable by adjusting what they're wearing based on the weather around you. If it's cold, add one more layer to what your baby is already wearing. If it feels hot, remove the extra layers so they don't get overheated.

There's also the option of maintaining a steady room temperature. The best range, according to research, is between 68 and 72 degrees Fahrenheit. That range has been shown to support better sleep and create a more relaxing space for your baby. These small adjustments can make a big difference in how well your baby rests.

7. Being Overtired

Sometimes babies cry in their sleep simply because they're overtired. You might notice this when your baby stays up too long past their wake window. Instead of settling down, their body starts sending mixed signals that confuse them. That can cause more frustration, and the crying often turns into screaming.

Some babies also experience restless legs or sore muscles from staying alert too long. These signs of tiredness are easy to miss during a busy day. That's why it helps to watch for sleepy cues like rubbing their eyes or turning their head away. When you catch those signals early, you can settle your baby before they become overtired.

8. Teething Discomfort

Your baby may be at the stage where the teeth start to come in, and comfort stops right there. This is one of those phases that brings a lot of discomfort, especially when they try to sleep. The pressure in the gums builds up, and your baby doesn't know how to deal with it, so they cry.

Many babies also experience diarrhea while teething, and that becomes another sign of what's going on at night. You may also notice more drooling or see your baby putting their hands in their mouth again and again. These signs usually show up together. To make things easier for you and your baby, you can use a chilled teething ring or gently massage their gums.

9. Having a Fever

It can be really hard for a baby to sleep when they are sick. If your baby seems extra fussy during sleep, it's worth checking their temperature. A reading of 100.4°F or above counts as a fever in babies, but the response depends on your baby's age.

You should call your pediatrician if your baby is two months old or younger and has a temperature of 100.4°F or higher. For babies between three and six months, the number goes up to 101°F. If your baby is older than six months and their temperature reaches 103°F or higher, that also needs attention. These numbers help you know when to take action without second-guessing.

10. Separation Anxiety

Separation anxiety starts to occur when your baby is around six months old and comes back in phases until they reach about 18 months. It's one of those signs that shows your baby is developing in a healthy way. At this stage, your baby starts to understand that people and things still exist even when they can't see them.

That idea might sound simple, but for a baby, it's a big shift. So when they wake up at night and don't see you nearby, they may feel uncertain and react by crying. This is normal, and it often means your baby just needs a little extra comfort before they settle down and fall back to sleep again.

11. Sleep Regression

If your baby suddenly cries at night for no obvious reasons mentioned above, it could be part of a sleep regression. These phases come and go during the first two years and usually show up when your baby reaches a big milestone. That might be learning how to roll over, sit up, or going through a growth spurt.

Even though it disrupts sleep, it is a sign that your baby is developing. Some experts call it a sleep progression instead. Your baby's brain and body go through new changes, and that shift often results in more restless and cry-filled nights. Once the phase ends, their sleep usually returns to a more regular rhythm again.

Part 2. Can Babies Cry From Bad Dreams?

Babies usually don't experience nightmares or night terrors until they're closer to two years old. If your child wakes up screaming or crying in the middle of the night, it can be their way of releasing built-up fear or stress.

The crying, the trembling, even the wild kicking or sudden movements are all ways their body reacts to that fear. In that moment, they are not misbehaving-they are overwhelmed and looking for a safe place.

What helps most is staying close and becoming the steady presence they can rely on. You can hold your child gently or pull them into your lap if they reach out.

Keeping a small light in the room also helps, especially if they open their eyes and want to find you. Let your child move around and release what they are feeling. Your calm response makes all the difference while that wave of emotion passes.

Part 3. See How Your Baby Behaves When Crying at Night Using HitPaw AI Video Generator

Now, there is a way you can see how your baby behaves when crying in sleep. Tools like HitPaw AI Video Generator allow you to type in a prompt and make a video of your baby going through the emotions that cause them to be fussy at night.

Here are the steps:

• Step 1.Visit HitPaw AI Video Generator and choose "Image to Video."

  

• Step 2.Now, upload an image of your baby sleeping at night. Next, in the prompt box, write the scenario in which your baby is crying with discomfort while sleeping. Then, select a resolution and the duration of the video.

  

• Step 3.Click "Generate" and then download it.

  

Part 4. FAQs of Why Do Babies Cry In Their Sleep

Conclusion on Why Do Babies Cry In Their Sleep

There are many reasons why do babies cry in their sleep. Some cry because they're hungry or uncomfortable from gas. Others wake up due to teething pain or a room that feels too hot or too cold. A few go through phases like separation anxiety or sleep regressions that throw off their rest. Once you understand what each cry points to, it gets easier to figure out what your baby might need.