If your baby was sleeping well and has suddenly started waking frequently at night, resisting naps, or rising very early in the morning, it can feel incredibly frustrating, especially when nothing obvious seems to have changed.
This is one of the most common baby sleep concerns I support families with at Little Dreams Consulting Chelmsford & Colchester. Parents often tell me, “They were such a good sleeper, what’s gone wrong?”
Be assured however, nothing has gone wrong. Sudden changes in baby sleep are very common, very normal, and almost always linked to development, or another reason that is very easy to explain.
Baby sleep is not linear (and that’s important to know)
Many parents expect sleep to improve steadily over time. In reality, baby sleep moves in phases. You have fab sleep and then suddenly it changes. This is really normal (and often) temporary as your baby grows, develops and changes.
A baby who once slept well hasn’t “forgotten” how to sleep. Instead, they are usually working through a new stage that temporarily affects how easily they settle and stay asleep.
Common reasons your good sleeping baby has stopped sleeping
1. A baby sleep regression
Sleep regressions are one of the biggest reasons a previously settled baby suddenly struggles with sleep. They are linked to rapid brain development and changes in sleep cycles.
Common baby sleep regressions happen around:
- 4 months (a permanent change in sleep structure)
- 6–8 months
- 12 months
During a regression, your baby may:
- Wake more frequently overnight
- Take shorter or more unsettled naps
- Fight bedtime
- Wake much earlier than usual
Although exhausting, regressions are a sign of healthy development.
2. Developmental milestones disrupting sleep
New physical and cognitive skills can have a big impact on baby sleep. Rolling, sitting, crawling, babbling and pulling to stand all place extra demand on your baby’s nervous system.
3. Wake windows or nap timings no longer working
Many babies practise these skills during the night, leading to sudden wakings even if they previously slept through.
As your baby grows, their sleep needs change quickly. Wake windows that worked well just weeks ago can suddenly result in:
- Overtiredness
- Short naps
- Early morning wakings
- Increased night wakings
This is one of the most common causes of disrupted baby sleep — and one of the easiest to fix with gentle adjustments. Read here about short naps and how to make small changes to resolve them.
4. Teething, illness or discomfort
Teething, reflux flare-ups, colds and ear infections can all cause a sudden breakdown in sleep. Even mild discomfort can make it harder for babies to settle and resettle between sleep cycles.
Once the discomfort passes, sleep often improves, although some babies need a little help returning to their previous patterns.
5. Separation awareness
From around 8–10 months, babies become much more aware of their parents’ presence and absence. This can lead to increased night waking and difficulty settling unless you are nearby. Separation Anxiety can feel really tough, but it is a normal and healthy part of emotional development.
6. Changes in how your baby falls asleep
During unsettled phases, it’s very common to offer extra help at bedtime, for example, feeding, rocking or holding your baby to sleep.
If your baby becomes reliant on this support to fall asleep, they may struggle to resettle independently when they wake briefly overnight.
This doesn’t mean you’ve created a bad habit. It simply means your baby may benefit from some gentle changes to how they fall asleep.
How to support your baby through disrupted sleep
- Review wake windows and naps
- Ensure your baby’s schedule is age-appropriate. Even small changes to nap timing or bedtime can dramatically improve sleep.
- Keep the bedtime routine calm and consistent
- A predictable bedtime routine helps signal safety and sleep, especially during regressions and developmental leaps.
- Respond with reassurance
- Supporting your baby through a difficult phase will not ruin their sleep. Responsive parenting builds security — and secure babies sleep better in the long run.
- Avoid changing everything at once
- When you’re exhausted, it’s tempting to try multiple strategies at the same time. Gentle, consistent changes are far more effective unless you are working with a Sleep Consultant to guide you through.
When to seek baby sleep support
If disrupted sleep is lasting more than a couple of weeks, or if exhaustion is affecting your confidence or wellbeing, I would love to help.
At Little Dreams Consulting Chelmsford & Colchester, I offer gentle, responsive baby sleep support for families with babies from newborn to 18 months. Every plan is tailored to your baby’s age, development and your parenting style.
Get in touch for a free 15 minute call to talk about your baby’s sleep and how I can help.
