It’s nearly impossible to tally all the ways sleep is essential for your child’s health and well-being. In fact, there’s not a single aspect of life that sleep doesn’t make better…or that lack of sleep doesn’t make worse! For babies and children, regular and adequate sleep allows their developing minds time to process new skills and experiences. Sleep consolidates their memories and improves motor development, vocabulary, attention, and mood…and so much more. Here, learn why getting enough ZZZs is critical for your little one.

Sleep helps keep the immune system healthy.

A child’s developing immune system needs adequate sleep to not only function properly, but to function optimally. During sleep, their little bodies produce a type of protein called cytokines. The main job of these proteins is to beat back infections and illnesses. Fun fact: When your bub is under the weather, their immune system automatically churns out more and more cytokines. And as an amazing bonus, some of these cytokines actually promote sleep, which—natch—helps produce even more infection-fighting cytokines. That means, when babies and toddlers (and grownups, for that matter) don’t get enough sleep, their cytokine levels dip, making it that much tougher to stave off—and recover—from illnesses. (Learn more ways to support your baby’s developing immune system.)

Sleep helps babies grow.

From birth to about 6 months, babies tend to grow about 1 inch a month, then about half an inch a month until their first birthday…which is a whole lot of growth in a short period of time! And one key factor into making it all go according to plan is sleep. That’s because when your love bug is visiting dreamland—notably when they’re in slow-wave, or deep sleep—their body releases human growth hormones (HGH). These hormones are connected to your bub’s height, their muscle mass, and their bone density. So, not getting enough ZZZs, can result in a decrease of growth hormone secretion…which can impact growth. In fact, research in the journal Sleep Medicine shows that children who slept less than 12 hours a day at 3 months old were significantly more likely to have shorter body length than those who snoozed longer, even after adjusting for any potential confounding factors. If your baby goes through a bit of a sleep rough patch, don’t worry too much. Experts note that when a child’s sleep routine is disrupted because of illness, they’ll often experience a growth spurt once they recover and return to their regular sleep patterns.

Sleep strengthens a baby’s memory.

Similar to adults, sleep benefits memory and language know-how in infants, both before and after learning, according to a report in the journal Nature and Science of Sleep. In short, getting adequate rest morphs initially weak memories into more stable memories, protecting them from getting lost in a sea of forgotten tidbits. To wit: Research out of Stanford University found that 6- and 12-month-old infants who napped for an average of 90 to 106 minutes four hours after learning a set of puppet-related actions, recalled significantly more the next day than no-nap babies. And a 2020 study in the journal Developmental Science noted that preschoolers who napped after storytime were better able to recall the story than their pals who did not nap. Another bonus to catching daytime ZZZs: Napping “clears” the hippocampus, the part of the brain that’s in charge of learning and memory, so that it can be filled again with new information upon waking up.

Proper sleep helps keep emotions in check.

It’s probably no surprise to parents that children who don’t get enough sleep are cranky, irritable, and more prone to tantrums. That’s because adequate sleep keeps children’s overall brain—including the parts that control emotions—functioning! The best way to illustrate this is to look at what happens when children don’t get enough sleep. For example, when compared to elementary school-age children who got the recommended nine to 12 hours of sleep a night, those who regularly got less ZZZs showed significant differences in certain brain regions responsible for not only memory and intelligence, but wellbeing, too, according to a 2022 study in the journal Lancet Child & Adolescent Health. And these differences correlated to more mental health problems, including depression, anxiety, and impulsive behaviors. Another study in the journal Academic Pediatrics found that children who get insufficient sleep in their toddler and preschool years old have a higher risk of poor emotional control, peer relationships, and attention at 7 years old. Although the study itself found no association between insufficient sleep during infancy and later neurobehavioral issues, the researchers note that sleep during infancy often predicts sleep during later ages. What that means is: It’s super-important to promote good sleep habits—and help your child get enough ZZZs—from the youngest age possible.

Sleep aids motor development.

Babies are noisy sleepers…and they’re active sleepers! But all those twitches, jerks, and spasms are not due to baby-sized dreams. Instead, researchers believe baby’s sleepytime movements are linked to sensory and motor development. Essentially, twitches that occur during sleep activate circuits throughout their developing brain, teaching your baby about their limbs and what they can do with them. More specifically, researchers found that sleeping babies between 3 and 7 months old produce a lot of sleep spindles, which are a specific pattern of brain waves, along the sensorimotor strip. This is where the brain processes sensory and motor information.

Adequate sleep helps families function!

When your little one isn’t sleeping, neither are you! That means, when babies and children are tired and grouchy and badly behaved thanks to poor sleep—you tend to feel all of that, too! That new-parenthood sleep deprivation has been known to worsen postpartum depression, marital conflict, it negatively affects breastfeeding, it even impacts DNA in a way that adds as many as seven years onto a new parent’s “biological age.” Plus, it’s much harder to be the parent you want to be when you’re bone tired. For example, caregivers who are short on sleep have more difficulty regulating emotions and embracing positive parenting, according to a report in the Journal of Family Psychology. Worse? Being overtired causes many parents—even those who know the ABCs of safe sleep—to make dangerous middle-of-the-night sleep decisions. A report in the journal Pediatrics found that 39% of parents who put their babies to bed safely, wound up doing something risky—like not returning their baby to the bassinet—after a nighttime wake-up. That’s a scary stat, especially since more than 90% of infants who die suddenly in their sleep are in an unsafe sleep environment.

Are children getting enough sleep?

Sadly, no. Research shows that roughly 35% of children between 4 months to 2 years old aren't getting adequate sleep. And that number appears to balloon as kids get older. According to a 2020 report out of Brown University, about half of children age 6 and up aren’t getting enough sleep—and those who are falling short are deficient in measures of “childhood flourishing,” like showing curiosity about new things, caring about schoolwork, staying calm when faced with challenges, and finishing tasks they’d begun.

How much sleep do babies need?

As babies grow and develop, their sleep needs change. Here’s how much sleep all newborns and babies need:

Sleep needs at 0 to 2 months: 14 to 18 hours 

  • Daytime sleep: 6 to 8 hours

  • Nighttime sleep: 8 to 10 hours* 

Sleep needs at 2 to 4 months: 12 to 16 hours 

  • Daytime sleep: 4 to 6 hours             

  • Nighttime sleep: 8 to 10 hours* 

Sleep needs at 4 to 12 months: 12 to 16 hours**

  • Daytime sleep: 3 to 5 hours

  • Nighttime sleep: 9 to 11 hours               

* Breastfed newborns wake about every 2 to 3 hours and formula-fed babies do so roughly every 3 to 4 hours

** About 62% of 6-month-olds can sleep in 6-hours stretches a night; 43% sleep for 8-hour stretches.

How much sleep do toddlers and big kids need?

Sleep needs at 1 to 2 years: 11 to 14 hours

  • Daytime sleep: 2 to 3 hours

  • Nighttime sleep: 9 to 12 hours

Sleep needs at 3 to 5 years: 10 to 13 hours

  • Daytime sleep: 0 to 1 hour

  • Nighttime sleep: 10 to 13 hours

Sleep needs at 6 to 12 years: 9 to 12 hours

  • Daytime sleep: 0*

  • Nighttime sleep: 9 to 12 hours 

*Children over age 6 should get all their sleep at night.

While every child is a little different, it is important to get as close as you can to the ideal total sleep time for your child’s age. To help get there, it’s first important to understand what baby and toddler sleep really looks like. Here’s some insight:

For more helpful tips on getting your baby to sleep, check out Dr. Karp’s best baby sleep advice. Got a toddler? No worries. Here’s the best toddler sleep advice parents need…now! 




  • Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement of the American Academy of Sleep Medicine. Journal of Clinical Sleep Medicine. June 2016
  • Uninterrupted Infant Sleep, Development, and Maternal Mood. December 2018
  • The Nemours Foundation, KidsHealth: Naps
  • Sleep Foundation: How Sleep Affects Immunity
  • Mayo Clinic: Infant and toddler health
  • Harvard Medicine: A Child’s Need for Sleep
  • Sleep duration and growth outcomes across the first two years of life in the GUSTO study. Sleep Medicine. October 2015
  • Infant sleep and its relation with cognition and growth: a narrative review. Nature and Science of Sleep. May 2017
  • Timely sleep facilitates declarative memory consolidation in infants. January 2015
  • Slow wave sleep in naps supports episodic memories in early childhood. Developmental Science. March 2021
  • Children’s Hospital of Philadelphia: Why Sleep Schedules Matter
  • Effects of sleep duration on neurocognitive development in early adolescents in the USA: a propensity score matched, longitudinal, observational study. The Lancet Child & Adolescent Health. October 2022
  • Prospective Study of Insufficient Sleep and Neurobehavioral Functioning Among School-Age Children. Academic Pediatrics. August 2017
  • Twitches emerge postnatally during quiet sleep in human infants and are synchronized with sleep spindles. Current Biology. August 2021
  • Sleep Quality in Women With and Without Postpartum Depression. November 2008
  • Postpartum sleep loss and accelerated epigenetic aging. Sleep Health. June 2021
  • Maternal stress, sleep, and parenting. Journal of Family Psychology. April 2019
  • Safe Sleep Behaviors and Factors Associated With Infant Second Sleep Practices. Pediatrics. May 2022
  • Circumstances surrounding sudden and unexpected sleep-related infant deaths, 2015 to 2020. The Daily. December 2021
  • Healthy People 2023: Increase the proportion of children who get sufficient sleep — EMC‑03
  • Sounding the Alarm on the Importance of Sleep: The Positive Impact of Sufficient Sleep on Childhood Flourishing. July 2020

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.