Why Do Babies Laugh in Their Sleep?
Babies may laugh during active sleep, a normal newborn sleep stage. During active sleep, babies may smile, twitch, move their eyes, or make short sounds. A brief giggle can be normal, while repeated laughing with unusual movements needs medical help.
Why babies laugh or smile while sleeping
A baby may make a brief laugh-like sound during active sleep. Of 383 newborn sleep smiles, 377 happened during active sleep. Many smiles also happened during quick eye movements.
Brief newborn laughs can happen even during the newborn period. No one knows why every sleeping laugh happens. A sleep giggle cannot prove your baby is dreaming. A giggle also cannot show happiness or discomfort.
What active sleep looks like in a newborn
Active sleep is a normal newborn sleep stage with more movement. Full-term newborns can spend about half their sleep in active sleep. Babies spend less time in active sleep as they grow.
During active sleep, you may notice:
- You may see quick eye movements under closed eyelids.
- Small twitches may move your baby face briefly.
- Arms, legs, fingers, or the mouth may move briefly.
- Your baby may suck, grunt, or make short sounds.
- Breathing speed may change for a few seconds.
- Your baby may smile or make a laugh-like sound.
Quiet sleep looks calmer and has fewer visible movements. At times, your baby may show signs from both stages.
How active sleep relates to REM sleep
Active sleep can look similar to REM sleep in older children. REM is short for rapid eye movement sleep. Newborn sleep still looks different because the brain is developing.
Older children and adults have REM and non-REM sleep stages. Baby sleep becomes more like older-child sleep with age.
A parent only needs to watch normal sleep behaviour at home. Only a doctor can diagnose a sleep disorder.
Does a sleeping laugh show your baby is dreaming?
A sleeping laugh cannot prove your baby had a funny dream. Babies cannot tell us what they saw or felt during sleep. Questions about dreams in babies and children remain unanswered.
Adult REM sleep has a strong connection with dreaming. One baby giggle cannot reveal any details about a dream.
Can gas make a baby smile or laugh?
Feeding, burping, passing wind, smiling, and sleeping can happen close together. Timing alone cannot prove gas caused the smile you saw. A baby may also relax after passing wind.
Some parents use the phrase gas smile. If your baby seems uncomfortable, watch feeding and crying together. Speak with a paediatrician when feeding discomfort keeps coming back.
A sleep giggle cannot tell you if your baby has gas pain.
How sleep smiles differ from awake smiles and laughter
A sleep smile differs from a smile your baby shares while awake. A newborn can smile in sleep without anyone talking nearby. While awake, babies start smiling back at familiar faces and voices.
At 2 months, most babies smile when you talk or smile at them. At 4 months, most babies chuckle when you try making them laugh. Some babies reach these milestones earlier or later.
| Behaviour | When you may see it | What is happening |
|---|---|---|
| Sleep smile | During active newborn sleep | Your baby smiles while asleep |
| Social smile | While your baby is awake with you | Your baby smiles back during interaction |
| Awake chuckle | During play around 4 months | Your baby starts laughing during awake play |
| Gas smile | Parent phrase | Passing wind may happen nearby without proving a cause |
Read when babies laugh out loud for awake laughter milestones. Try playful ways to make a baby laugh during comfortable awake play.
Can a sleep giggle tell you if your baby is healthy?
One sleep giggle cannot tell you how healthy your baby is. It also cannot show happiness, immunity, or brain development. Awake smiles, feeding, movement, sounds, and play tell you more.
Watch those signs along with age milestones during awake time. For wider family wellbeing, read raising healthy and happy kids.
For older-child nutrition, see foods supporting immune health.
What you notice and what to do
Watch what happens during the whole episode, beyond the laugh alone. Check breathing, skin colour, body movement, and your baby response. Notice if the same episode happens again.
| What you notice | What to do |
|---|---|
| One brief giggle, usual lip colour, easy breathing | Watch quietly and let your baby sleep |
| The same laugh happens again and again | Note what happens and contact a paediatrician |
| Laughter with staring, stiffening, or repeated shaking | Contact a paediatrician |
| Blue lips, severe breathing trouble, or difficulty waking | Seek urgent medical help |
When should sleep laughter concern you?
Call a paediatrician when repeated laughs look alike each time. Call sooner when your baby stares, stiffens, shakes, or becomes hard to wake.
A gelastic seizure is a rare seizure that causes sudden laughter. The laugh may sound forced without anything funny happening nearby.
Contact a paediatrician when repeated laughter comes with:
- Your baby becomes very hard to wake.
- Your baby stiffens or shakes in the same way.
- Your baby has a fixed or vacant stare.
- Lip smacking, swallowing, or unusual grunting keeps happening.
- The same type of episode happens again and again.
- You notice new changes in behaviour or development.
Some laughing seizures can begin during infancy. Some episodes last around 10 to 20 seconds.
If shaking is your main concern, read why babies shake while sleeping.
What should you watch during an unusual episode?
Watch what happens during the whole episode. Note its length, eye movement, body movement, breathing, and skin colour. Check how your baby responds after waking.
A short video can help a paediatrician see what happened. Make a video only when you can watch your baby safely. Seek urgent help for blue lips or severe breathing trouble.
Get urgent help if your baby becomes floppy or very hard to wake.
Safe sleep rules remain the same
Use the same safe sleep rules after a sleep giggle. Place your baby on the back for every sleep. Use a firm, flat infant sleep surface every time.
For safe baby sleep, use a sleep space without soft objects. Remove pillows, blankets, soft toys, and other soft items. Choose a crib, bassinet, portable crib, or suitable play yard.
A sleep giggle needs no pillow, incline, or position change.
How can parents support better baby sleep?
Low lights and quiet voices can make nighttime calmer. Feed or change your baby whenever needed. Repeat the same short bedtime routine each night.
Very young babies may still wake many times overnight. Baby sleep patterns can change a lot during the first year. See nighttime sleep tips for babies for more bedtime ideas.
You can also read how to help a baby sleep at night.
Common questions about babies laughing during sleep
What if my baby wakes crying after laughing?
A sleep laugh cannot prove your baby had a nightmare. Babies may wake crying from hunger, discomfort, illness, or wet nappies. Check hunger, nappy needs, temperature, and illness signs first.
Read common reasons babies cry and ways to soothe them. You can also see ways to calm a crying baby.
Is changing breathing during sleep normal?
Newborn breathing can change for short periods during sleep. During sleep, newborn breathing may pause for a few seconds. Breathing may also become quicker for a short time.
A smile cannot tell you if breathing is safe. Watch chest movement, lip colour, feeding, and overall response.
Seek urgent medical help when:
- Your baby struggles visibly with every breath.
- Your baby has blue lips or a blue tongue.
- Your baby becomes too breathless to feed well.
- Severe breathing trouble continues without easing.
- Your baby becomes floppy or very hard to wake.
Can teething cause sleep laughter?
Teething can disturb sleep and make babies more unsettled. Common teething signs include sore gums, drooling, chewing, and fussiness. A sleep giggle cannot show that teething bothers your baby.
Can reflux cause sleep laughter?
A sleep laugh cannot tell you if your baby has reflux. Common reflux signs in babies include bringing up milk, coughing, hiccupping, gulping, and unsettled feeding. Speak with a doctor when feeding problems keep coming back.
Should you tickle a sleeping baby for a laugh?
Let your baby sleep and save playful touch for comfortable awake time.
Should sleep laughter happen every night?
No fixed number of sleep laughs is expected each night. Some babies show many smiles, twitches, and little sounds. Other babies sleep with fewer visible movements.
What parents should remember
A brief giggle can happen during normal infant sleep. Contact a paediatrician when repeated laughter comes with unusual movements. Blue lips, breathing trouble, or difficulty waking need urgent medical help.
