As you're probably aware, babies sleep a lot. In the early weeks (and sometimes months) perhaps seemingly more in the day than at night.

How long they manage to stay awake for during the day, between sleeps, is very short but gradually increases. You may have seen these periods referred to as Wake Windows.

Your tiny baby may only be able to stay awake for 30-45 minutes, enough time for a nappy change, a feed and a cuddle before going back to sleep. This might gradually extend to an hour towards 6 weeks and and then, somewhere along the way, closer to 1.5hrs or even 2 or 2.5 by 3 months.

Remember, babies aren't robots. So your 4 week old may be a classic 40 minute napper, followed by 30 mins awake while your neighbour's baby of the same age feels fuelled by that 40 minutes to stay awake a full hour or more. Wake Windows are based on averages for each age bracket and, as with all averages, some will be above it and some below.

If you notice patterns in how long your baby can last before getting tired after a full sleep cycle, you may start to be able to predict when each days naps may happen. But remember, if they haven't managed 1 sleep cycle during the previous nap, they'll likely get tired sooner during their "normal" wake window.

You may see people advise you to watch the clock to get your baby's sleep right…and yes, having an idea of when your baby woke, after a nap of however long, and the average amount of time your baby has recently been managing between naps may help you to guess when they may get tired again and pre-empt it. Some people find this clock method helps them feel more in control.

But don't forget to watch your baby. If you notice those early sleep cues, listen to your baby before you decide they're not "due" to be tired for another 20 minutes (they can't read the time yet). Wake Windows definitely have their uses, helping you have an idea of how long your baby is likely to be awake for between naps as they grow and develop! 

Just remember though: just like you or I, if the last stretch of sleep wasn't as long as normal, perhaps not even a full sleep cycle (a cat-nap if you will), the likelihood is that tiredness will hit earlier, after a shorter window of wakefulness, than if a longer sleep had been had! 

So, keep watching your baby not just the clock!