Why Split Nights Happen—and How to Fix Them

Parents often expect their babies to wake up in the night, usually for a quick feeding or some comfort. But sometimes, out of nowhere, a baby wakes up at 2 a.m.—not crying, not fussing—just wide-eyed and ready to play. For hours.

This wide-awake period, often called a split night, can leave caregivers confused and exhausted. Even with a regular bedtime and consistent sleep training, some babies wake up full of energy and curiosity, as if it’s morning already. But when parents understand why these split nights happen, they can respond with less frustration and more confidence, finding ways to ease their baby—and themselves—back into restful sleep.

Understanding Split Nights

Babies or toddlers experience split nights when they wake up in the middle of the night and stay awake for a long stretch, often lasting one to three hours. Unlike brief, normal awakenings, the child may be alert or even playful during this time.

Many factors, such as discomfort from constipation, growth spurts, or the development of new skills, can cause these long periods of wakefulness. While anyone can have an occasional restless night, split nights become a concern when they happen most nights for over two weeks. When this happens, it often signals a persistent sleep problem that may need attention.

Why Split Nights Happen

Split nights usually happen when the body’s natural sleep triggers—circadian rhythm and sleep pressure—no longer line up properly. Circadian rhythm is the body’s internal clock that tells it when it’s time to rest, often based on darkness and melatonin levels. Sleep pressure is the drive to sleep that builds up the longer someone stays awake. In babies, these two systems should work together, but several factors can keep that from happening.

Napping patterns during the day play a major role. When babies take notably long or frequent naps, they may use up the amount of sleep they need before nighttime begins.

For example, if a child naps for five hours spread throughout the day, this can leave less “sleep need” for the night. As a result, they may wake up during the night feeling alert. Their sleep pressure drops, and it takes a while before enough sleep pressure builds up again for them to fall back asleep.

Early bedtime is another factor. When caregivers schedule bedtime too early, especially after a day with fewer naps, some children end up lying in bed longer than their bodies actually require. This extended time in bed can also disrupt the balance between circadian rhythms and sleep pressure, leading to long periods of wakefulness in the middle of the night.

Managing nap lengths and timing, along with having a bedtime that suits the child’s age and sleep needs, can help reduce the chances of split nights. Careful tracking and small changes can make a noticeable difference in bringing the sleep pressure and circadian rhythm back into alignment.

How to Fix Split Nights

To help babies avoid split nights, caregivers should adjust both daytime sleep and bedtime. Babies aged four to 12 months usually need a total of 12 to 16 hours of sleep over 24 hours, while toddlers may need 11 to 14 hours. If a baby is sleeping too much during the day, shortening each nap can be useful. Gently waking the baby a bit earlier from naps or extending the time before the next nap can help reduce night wakings.

Every baby’s sleep needs can vary, so it may take some trial and error to find the right nap length. Some babies benefit from short naps of 30 to 45 minutes, while others may need to drop a nap depending on their age and stage. If a very early bedtime seems to contribute to split nights, parents can try shifting the schedule later in small steps.

Caregivers should aim for a balance, making sure babies have enough awake time during the day to become tired enough for bedtime. At the same time, it’s important not to let babies get overly tired, as this can lead to fussiness and also disrupt sleep. The goal is for the baby to have just the right amount of time awake to build sleep pressure, which helps them fall asleep and stay asleep at night.

How Often Do Split Nights Occur?

Split nights are quite frequent across different ages, not just in newborns. Babies under four months often have split nights as part of their usual sleep habits. However, children from five months up to toddlers may also experience these periods. Even at age two, many children can wake up for 20 to 30 minutes during the night and might need help falling back asleep.

Should You Just Wait and See?

When a child experiences nighttime wakefulness, many parents wonder if they can simply allow the phase to pass. Sometimes, a baby or toddler will stay awake but remain calm and content. In these situations, there is no need to intervene if the child is happy and safe. Allowing a child to relax on their own can help them rebuild sleep pressure so they are ready to rest again soon.

If the child becomes upset or distressed during these wakeful periods, caregivers can connect with soothing actions like singing a gentle song or offering a long, comforting hug. These calming measures often reassure children who struggle with being alone during the night. If split nights are only happening for a week or two, waiting it out is usually a reasonable approach.

Some children, especially toddlers, may wake more often if they feel disconnected after a busy day. Spending extra time together in the evening and using comfort items, such as a caregiver’s clothing or a familiar scent, may ease nighttime separation. For older toddlers who understand routines, a visual cue like a special clock can guide them about when to stay in bed and when it’s time to get up.

Other Factors That May Disturb Sleep

Night wakings in babies are not always caused by hunger or a dirty diaper. Sometimes, waking your baby for a feeding or a diaper change can actually make it harder for them to fall back asleep, unless they truly need it. Caregivers should think about all the possible reasons a baby might be awake for long stretches at night rather than sleeping in longer blocks of time.

Several things can contribute to these disruptions. Babies may be gassy after trying a new food or if their digestive system is adjusting. Issues like reflux can also make sleep uncomfortable.

Not getting enough physical activity or stimulation during the day is another common cause. Babies who don’t have many chances to move freely might be more likely to wake up and want to practice skills like rolling, sitting up, or babbling. Daytime play on the floor or tummy time gives them a chance to work on these skills in a safe place so they are less likely to practice in the crib at night.

Cognitive development also plays a role. As babies’ brains process new skills and information, their sleep may be lighter, and they might try to master these abilities during the night. Ensuring babies have enough stimulation and practice opportunities during the day can make it easier for them to rest at night.

Adjusting nap times or bedtime schedules and keeping routines consistent can help. If these changes do not help and wakings continue, families should check with a healthcare provider to rule out medical concerns such as sleep apnea. Sometimes, sleep consultants can offer extra guidance and support for families struggling with persistent night wakings.

Before turning to professional help, there are also simple strategies families can try at home. Create a calm sleep space. Use white noise to block out sudden sounds. Shorten naps to support better nighttime rest. Simple cues like a blanket or lullaby can signal bedtime and help babies settle. With a few small changes, split nights often improve, leading to better sleep for everyone.