Why Does My Baby Cry in Their Sleep?
Updated September 2025 · 4 min read
Babies often whimper, grunt or briefly cry in their sleep without waking, because they spend a lot of time in light, “active” sleep and are still learning to move between sleep cycles. It’s usually normal. Pausing for a moment before rushing in gives your baby the chance to resettle — but if the crying is inconsolable, or comes with fever, pain or signs of illness, contact your doctor.
- Whimpers and brief cries in sleep are common and usually normal.
- Babies have lots of light, “active” sleep, especially in the early months.
- Pause before intervening — your baby may resettle on their own.
- Seek advice if crying is inconsolable or paired with illness or pain.
A lot of baby sleep is “active” sleep
Newborns and young babies spend a large share of their sleep in light, active (REM-like) sleep. During it they twitch, grimace, grunt, breathe irregularly and make little noises — including whimpers and brief cries — all while still asleep. It can sound dramatic, but it’s a normal part of how babies sleep.
Learning to link sleep cycles
Babies surface briefly between sleep cycles, just as adults do. The difference is that they’re still learning to settle themselves back down, so those surfaces can come with a cry. Often, if you wait a moment, they drift back off without fully waking.
Should you go in?
A short pause is worth it. Rushing in at the first sound can wake a baby who was about to resettle. If the crying continues, builds or your baby clearly wakes, then respond as you normally would — a baby who is genuinely awake and crying may be hungry, uncomfortable, wet or want comfort.
Common everyday causes
- Hunger — especially in the early months of frequent feeds.
- Wind or a dirty nappy.
- Teething or a developmental leap can make sleep lighter for a while.
- Too warm or too cold — check the layers and room temperature.
When to seek advice
Trust your instincts. Contact your health visitor, GP or paediatrician if the crying is inconsolable, sounds like pain, or comes alongside a fever, poor feeding, vomiting, unusual breathing or any sign of illness — or simply if you’re worried. You know your baby best.
Frequently asked questions
Is it normal for a baby to cry in their sleep?
Yes. Babies spend a lot of time in light, active sleep, during which they often whimper, grunt or briefly cry without waking. Itu2019s usually normal.
Should I pick up my baby when they cry in their sleep?
Pause for a moment first u2014 many babies resettle on their own. If the crying continues and your baby wakes, respond as you normally would.
When should I worry about my baby crying in their sleep?
Seek advice if the crying is inconsolable or sounds like pain, or if it comes with fever, poor feeding, vomiting, unusual breathing or other signs of illness u2014 or whenever youu2019re worried.
Sources
Safe-sleep guidance in this article reflects the recommendations of bodies such as the American Academy of Pediatrics (AAP), the UK’s NHS and The Lullaby Trust. It is general information, not medical advice — always follow the guidance of your own paediatrician, midwife or health visitor.