Looking for night diapers in large sizes? Then you probably have a child who has outgrown the toddler sizes but still needs a diaper that stays leak-free for ten, twelve hours. Many brands stop early. We don't. Bammies cover up to 20 kg, and in this guide we untangle how size, fit and absorption work together when your child is bigger and the night is long.
Why does the night diaper leak as your child gets bigger?
The short answer: the diaper is usually too small. A bigger child pees more at once, sleeps for longer stretches and moves more in their sleep. If the diaper then sits at the lower end of the weight range, there's too little material where the liquid needs to be absorbed. The result is leaks at the back, between the legs or straight through.
These are the most common causes we see with bigger children:
- Size too small. Leaks at the back and between the legs are often a sign it's time to size up.
- Leak guards folded inwards. The elastic around the legs needs to be fluffed out to do its job.
- The diaper sits too low at the back. Children who sleep on their tummy or back need extra height behind.
- The wrong style for your child's build. Sometimes a pant diaper fits better than an open diaper, or the other way round.
In other words: the absorption can be as good as you like, but if the liquid never ends up in the diaper, it won't help. Size and absorption have to go hand in hand.
The right size for bigger children: The Toddler, The Kiddo and The Explorer
Our three largest sizes are built for children who run all day and sleep deeply at night. Weight ranges are always a guide. How your child is built around the tummy, legs and back matters at least as much.
- The Toddler, 8 to 14 kg. The transition size. This is where many children start sleeping longer nights, and it's often where the first night leak shows up. Also available as a pant diaper.
- The Kiddo, 10 to 16 kg. For children who climb, protest at diaper changes and need plenty of room for liquid at night. Also available as a pant diaper.
- The Explorer, 14 to 20 kg. Our largest open diaper. For older children who still need a night diaper when many other brands have already run out of sizes.
Good to know: our diapers run slightly larger than many other brands. If your child is between two sizes, we recommend the larger size in open diapers and the smaller size in pant diapers. Still leaking at night despite the right weight? Try the next size up. It's the single most common fix.
Open diaper or pant diaper at night?
Both work. The difference is in the fit and in how your child sleeps.
Open diaper
With tape tabs you can adjust how snug the diaper sits at the waist and pull it up a little higher at the back. That makes it a safe choice for children who sleep still or spend a lot of time on their back, where leaks at the back are the biggest risk.
Pant diaper
Pant diapers generally have a bigger waist and leg opening than open diapers in the same weight range, and they move with the body when your child rolls over. For kids who spin around in bed, or who have started potty training and want to pull the diaper up themselves, a pant diaper is often the easiest choice for the night. You'll find our whole pant diaper range in the pant diapers monthly box.
What a large-size night diaper needs to handle
A big diaper needs more than just more fabric. It needs to take up the liquid fast and keep it away from the skin all night long.
- Up to 12 hours dry. The diaper is made to last a whole night without a change.
- Bamboo fibers that absorb. Bamboo fibers can absorb up to three times more liquid than regular cotton, which helps keep your child dry for longer.
- Breathable. The layer against the skin is 100% bamboo, soft and airy. You'll notice it in the morning.
- Plant-based wetness indicator. So you can check how things look during a quick night check without waking anyone.
And one more honest thing: no diaper in the world stays leak-proof if it's sitting wrong. That's why size is always step one.
Quick check before lights out
Three seconds that save a sheet change at 3 AM.
- Fluff out the elastic around the legs so the leak guards stand up and aren't folded inward.
- Pull the diaper up high at the back.
- Check that about two fingers fit in the waist. Snug enough, without gaping.
- Change into a fresh diaper right before bedtime, even if the old one isn't full.
- If it still leaks, go up a size. If the diaper fills up fast, that's the same signal.
Kind to the skin, even after a whole night
Twelve hours is a long time for a little bum. That's why the layer against your child's skin is 100% bamboo, with no lotions or perfumes. The diaper has the Dermatest rating Excellent, and we stand behind it: if the diaper causes a rash, you get your money back. On top of that, the diaper is made with significantly less plastic than many conventional diapers. Less plastic. More logic. Especially when it comes to a diaper that's meant to stay on all night.
Many parents tell us the night is exactly what decides whether they stay with us. As one customer wrote: "Soft, flexible and leak-proof. Gentle on the skin."
Unsure about the size? We'll help
Finding the right large-size night diaper can take a couple of tries, and that's completely normal. If it leaks even though you've followed the tips above, get in touch with your child's weight, age and which size you've tried. We'll send samples in another size free of charge, and if there are leakage or quality issues we offer a free replacement box.
Want to try for yourself first? Our sample kit for The Explorer and sample kit for pant diapers 8 to 14 kg let you test a few nights before ordering a whole box.
Next step: choose your night diaper
Has your little one passed 8 kg and started leaking at night? Start by going up a size. Does your child spin around in their sleep or has potty training begun? Then pant diapers are often the way to go. Pick a size based on your child's latest weight in the pant diapers monthly box, and a whole month of diapers is delivered to your door with free shipping. No commitment. Switch size, pause or cancel whenever you like.
Dry nights. Less plastic. More sleep for everyone in the house.
