The 8 to 10 month shift is a big one, and your baby is doing some of the most extraordinary growing of their first year. The sleep changes are part of that.
If your baby was sleeping reasonably well and has suddenly started waking through the night, fighting naps, calling out for you, or refusing to be put down, you have probably found yourself searching "8 month sleep regression" at 2am. You are very much not alone. This stage catches so many families off guard. The first year felt like it was getting easier, and now suddenly it isn't.
Please know this isn't a regression in the sense of going backwards. It's a developmental leap forward, and once you understand what's happening, the sleep changes start to make a lot more sense.
What's actually happening at 8 to 10 months
Around this stage, your baby is going through one of the biggest developmental phases of the first year. Their brain is wiring at speed. They're learning that you exist when they can't see you (a huge concept). They're often working on big motor skills like sitting, crawling, pulling up. They're starting to understand more language. They're noticing the world in a much richer way.
All of that growth is happening in the same brain that's also doing the work of sleep. So sleep gets a bit choppy. Their nights become more fragmented. Their naps may shorten or lengthen. They might suddenly need much more help to settle, or wake more often calling for you.
This is also when separation worries often emerge for the first time. Your baby has just figured out that when you leave, you still exist, but they don't know when you'll come back. That makes bedtime, naps, and middle of the night separations feel much harder for them.
This isn't your baby being difficult. It's your baby's brain doing the most important work it has ever done.
Why it can feel like a regression
The reason this shift can feel like a regression is that, for a while, your baby was sleeping in a relatively settled pattern. You had built rhythms, expectations, ways of doing things. Now those things don't seem to work the same way. The way babies move through sleep cycles hasn't changed, but their awareness of those transitions has, and their need for you in the middle of them has too.
It's a bit like the 4 month shift in that it represents a new stage rather than a step back. Your baby isn't unlearning sleep. They're growing into a new version of themselves that needs you slightly differently.
What helps
The most helpful shift is to lean in rather than pull back. Your baby needs more of you right now, not less. This is not a phase to "push through" by reducing your support. Extra cuddles, extra closeness, slower transitions, and lots of reassurance all help.
Watch for opportunities to practise separations during the day in low pressure ways. Peek a boo, brief moments of stepping out of the room and coming back, naming what you're doing ("Mum's in the kitchen, I'll be back"). All of this builds the brain pathways that help your baby trust that you always come back.
Keep your bedtime rhythm consistent. Even if everything else feels chaotic, the predictability of bedtime is anchoring. Offer extra comfort, more contact, more presence at this stage, knowing that the increased connection is exactly what your baby's brain is asking for.
This phase usually softens within 2 to 6 weeks as your baby's brain integrates the new skills. The sleep often comes back, often in a slightly more mature form than before.
If you'd love a deep, gentle understanding of what's happening in your baby's brain at every stage, including how shifts like this affect sleep and how responsive caregiving builds the foundation for better long term sleep, the Your Baby's Brain guide walks you through it. It's a deeply reassuring resource that makes phases like this feel less scary and far more understandable.
This stage is hard. Really hard. But your baby is doing magnificent work, and so are you.
