One month your baby settles into a beautifully predictable sleep pattern. The next, they're waking every hour, resisting naps, or fighting bedtime with real intensity.
If this feels disorienting, take heart: it's one of the best-documented experiences in early childhood sleep. It's called a sleep regression, and nearly every family encounters it at some point in the first two years.
What Does the Research Say a Sleep Regression Is?
A sleep regression describes a temporary disruption to a child's sleep patterns, following a period of settled sleep. It isn't a step backwards developmentally. Often, it's the opposite.
Researchers link these disruptions to bursts of brain growth. As new neural pathways form to support an emerging skill, sleep can be disrupted while that learning is consolidated.
Most regressions resolve within two to six weeks, though every child's experience is individual. Some children move through certain stages with barely a ripple.
It's also worth noting that not every sleep disruption is a true regression. Teething, illness, travel, and changes in routine can all cause short-term sleep upheaval that looks similar. If disrupted sleep coincides with one of the developmental windows below, a regression is the more likely explanation.
When Do Sleep Regressions Typically Occur?
While every child's development is unique, research points to a few key windows where sleep disruption is more likely.
- 4 months: Often the first regression parents notice, and typically a permanent shift rather than a temporary one. Your baby's sleep cycles mature from a newborn pattern into a more adult-like structure, with distinct light and deep phases, leading to more frequent waking between cycles.
- 8 to 10 months: This window often coincides with crawling, pulling up to stand, and the emergence of separation anxiety, all of which can disrupt settling and night waking.
- 18 months: Frequently cited as the most challenging regression, driven by a surge in independence, big emotions, and boundary testing at bedtime.
- 2 years: Continued growth in language, imagination, and independence can bring a further dip in sleep, sometimes alongside new fears or the transition out of a cot.
Why Do Sleep Regressions Happen?
Sleep regressions are closely tied to bursts of physical, cognitive, and emotional development, and separation anxiety plays a significant role at several of these ages.
According to Raising Children Network, separation anxiety is a normal part of development that typically begins around six to seven months and peaks between fourteen and eighteen months.
Understanding the developmental basis for these shifts can make it easier to respond calmly, rather than reading them as a behavioural issue that needs correcting.
Evidence-Informed Strategies to Help at Home
- Keep routines consistent: a predictable sequence before sleep gives your child something familiar to anchor to, even while other things feel unsettled.
- Offer reassurance without new habits: extra comfort is fine during a regression, but where possible avoid introducing sleep associations you'll need to unwind later, such as feeding to sleep every time.
- Watch wake windows: an overtired child typically sleeps worse, not better, and appropriate wake windows shift as your child grows.
- Allow yourself grace: regressions are genuinely tiring, and it's reasonable to lower the bar elsewhere while you move through one.
- Trust that it's temporary: most regressions ease on their own within a few weeks as your child consolidates their new skill.
How Papilio Supports Sleep During Regressions
At Papilio, our approach to rest is grounded in our Lifelong Learning Curriculum, which recognises sleep, rhythm, and routine as foundational to a child's cognitive and emotional development, not simply a break in the day.
Every child has an individual rest plan, reviewed regularly and shaped in partnership with families. If your child is moving through a regression at home, our educators can adjust their routine with you.
Our rooms are designed for calm, low-stimulation wind-downs, with familiar comfort items and consistent, responsive educators, an approach informed by current research into infant and toddler sleep.
We also keep families closely informed. If your child's sleep shifts while they're in our care, educators will let you know and share what settled them, so you can align routines between home and centre during the regression.
For more on supporting sleep at home, see our guides on creating calm, safe sleep for babies, toddlers and preschoolers and tips from an educator to help your child sleep better.
If your child's sleep disruption lasts longer than a few weeks, or seems out of step with their usual development, it's worth discussing with your GP or child health nurse.