The 4 Season® Big Kid Sleep Bag keeps your child at a perfect temperature throughout the night, year-round. That means there’s no need to worry about which weight sleeping sack to use, or whether your child will be too hot or cold while sleeping – they’ll always be just right!
Made with super-fine and supremely breathable merino wool, it helps keep your kid warm when it’s cold and cool when it’s warm. That temperature regulation means that your child will sleep comfortably throughout the night– and that means a better night's sleep for you too. Cuddly-soft organic cotton outer adds to the comfort as it's perfect for the most delicate skin.
It comes in a universal size that fits kids from 4 to 6 years. It saves you buying a different sleeping bag for different seasons, as well as buying larger ones as they grow. You just need one Woolino sleep bag for your child that will fit for 2 years.
Premium Natural Fabrics Silky-soft hypoallergenic merino wool lining and the finest organic cotton outer.
4 Season use Unlike other brand sleep sacks that come in either winter or summer weight/TOG rating, the Woolino 4 Season Sleep Bag can be used year-round. It’s suitable for room temperature 63-75F (17-24C). Because of merino’s unique ability to regulate body temperature, it helps keep your child warm when it's cold and cool when it's hot.
Grows with your child It is designed to fit kids 4 to 6 years old.
Excellent value It saves you buying a different sleep bag every few months. It’s the only sleep bag your child will need, in winter or summer, for 2 years.
Designed to be practical It features double shoulder snaps and a two-way side zipper, so you can open it completely flat for easy dressing, or you can open just the bottom. Zipper-pull guards protect child's skin and discourage child from chewing on the zipper pull.
Replaces loose blankets Helps your child to stay covered through the night.
Free shipping in the USA (Expected Delivery: 3-6 Business Days) on orders of $95 USD or more.
VIP Shipping: Your order is processed within 1 business day, even during high-volume periods. Enjoy faster delivery (estimated 2–4 business days) for a flat rate of $10 USD, available at checkout.
Express international shipping (Expected Delivery: 2-5 business days) starting at $14.99 USD.
Additional information about our shipping policy can be found here.
Machine wash on low (100°F max), use wool or mild detergent. Close zipper. Can be tumble dried on No Heat or Air Dry setting. Hang to dry whenever possible. To refresh and reduce washing, turn garment inside-out and air often.
We do not recommend sizing up.The sleep bagshould be well-fitted around your child's upper body for a safe and secure fit. We recommend using our sizing guidelines to determine the correct size based on your child's age, height, and weight. Your baby should not be below the minimum recommended weight.
Setting the standard for textile safety, from yarn to finished product, Woolino sleep sacks and clothing bearing the OEKO-TEX® STANDARD 100 label (23.HUS.59156, Hohenstein HTTI) have passed safety tests for the presence of over 1000 harmful substances;
Woolmark® and RWS certified merino wool (Responsible Wool Standard - cruelty-free, mulesing-free wool);
GOTS certified organic cotton.
What is a baby sleep bag or sack?
A baby sleep bag, also called a wearable blanket or sleep sack, is a bag-like garment or covering worn by infants for sleeping. It replacing loose blankets in the crib that can cover your baby's face and interfere with breathing.
Since 2005, The American Academy of Pediatrics has recommended the use of wearable blankets for safe sleep. Unlike regular blankets, a wearable blanket or sleep sack is worn over your child's sleepwear, so it won't be kicked off and baby stays covered all night. The sleep bag will become part of your child's bedtime routine, providing a sense of security and comfort.
What is the TOG rating of your sleep bags? Are they winter or summer weight?
Our 4 Season baby sleeping bags are designed to be worn year round. They are made from 100% natural breathable fibers and contain NO synthetic filling. Therefore, they do not have a fixed TOG. The fine merino wool lining helps naturally in regulating baby’s body temperature, keeping baby warm in winter and cool in summer.
Woolino sleep bags are recommended to be used in room temperatures 63-75F (17-24C). Simply adjust the layers of sleepwear worn under the sleeping bag to suit the nursery temperature. You can find our suggested dressing guidelines on the back of the room thermometer that comes with every baby sleep bag.
What is the difference between Woolino Ultimate (universal size) and Woolino Basic Baby Sleep Bags?
Both collections have same weight fabrics, merino wool lining and organic cotton outer. The differences are:
Woolino 4 Season Ultimate Baby Sleep Bag has universal sizing: 2m-2yr, underarm snaps for adjusting the size of the armholes, travel slots for use in car seats, strollers, bouncers etc., & both shoulder snaps.
Woolino 4 Season Basic Sleep Bag has simpler design: no snaps and no travel slots; it comes in traditional sizes: 0-6, 6-18, 18-36 months.
Woolino sleep bags sizing chart?
We do not recommend sizing up.The sleep bagshould be well-fitted around your child's upper body for a safe and secure fit. We suggest using our recommended sizing guidelines to find the correct size based on your child's age, height, and weight.
When can my baby start using Woolino Ultimate Baby Sleep Bags in size 2m-2yr? How long will my baby fit in this Woolino sleeping bag?
Woolino Ultimate Baby Sleep Bags provide an excellent value as they are designed to fit an average size baby from about 2 months up to 2 years of age. You may start using your sleeping bag when you feel your baby is too big to be swaddled and is breaking out of it. Please use the under-arms snaps to adjust the fit for smaller babies. Our minimum recommended weight is 10lb. or 4.5 kg.
When should I use the under-arm adjustment system?
In general, you need to use the under-arm snaps for babies up to 6 months old. However, this depends on baby’s size, so for smaller babies you may have to use them longer. Please keep in mind that the underarm snaps are to be used for safety reasons, so that the sleep bag fits snugly around baby’s upper body and doesn’t climb up baby’s face.
Do I need more than one Woolino sleeping bag?
Yes, we recommend having two Woolino baby sleeping bags. It is always useful to have a spare sleep bag when one is being washed, to keep at grandparents' place or if baby requires a quick change in the middle of the night. Please enter code BOGO20 at checkout to receive our buy one item, get one item 20% off promotion. This promotion cannot be combined with any other offer.
Won’t wool itch my baby’s skin?
Absolutely not. We use only superfine merino wool, which unlike the traditional wool, feels like silk against baby’s delicate skin. In fact, because of its softness and unique breathability, it is perfect for helping treating conditions such as heat rash and eczema.
Isn’t merino wool too hot for warm temperatures/climates?
Our merino wool baby sleeping bags are perfect for year-round wear in nurseries with room temperatures 63-75F (17-24C). Simply adjust the layers of underwear or sleepwear worn beneath the sack to suit the room temperature. Merino creates a micro-climate around your baby’s body, gaining or losing heat as required to produce warmth in cool conditions and enhance cooling effects in warm conditions.
What should my baby wear when sleeping in a Woolino 4 Season Sleep Bag?
We recommend sleepwear made of natural and breathable fabrics like cotton or merino wool. Please refer to the dressing guide we provide (also on back of your Woolino room thermometer) as general recommendations on how to dress your baby depending on the room temperature. Woolino pajamas are ideal for layering or to wear inside a Woolino sleep bag. The temperature in most rooms will rise and fall throughout the night, and the merino fiber has the remarkable ability to regulate your baby's body temperature.
How do I know if my child is hot or cold?
Please check if your baby is hot or cold while sleeping by touching her tummy or behind her neck. Touching baby’s hands and feet are not good indications of their actual body temperature.
Why don’t the sleeping bags have sleeves? Won’t my child get cold?
Our baby sleeping bags are sleeveless to ensure air circulation around baby’s chest. Babies that sleep with traditional sheets and blankets rarely sleep with their arms underneath the blankets. We recommend layering under-garments to ensure your child is perfectly comfortable in their sleeping environment. It is normal for babies to have cold hands and feet due to their still-developing circulation systems and it is not an indication that they are cold. Checking behind baby’s neck or his/her tummy will give you better indication of baby’s body temperature.
Does the sleep bag need to be washed before the first use?
It is not required to wash your Woolino sleep bag before wearing. When you wash it, please follow the care instructions carefully.
Why does wool smell when it gets wet?
There is an odor associated with wet wool, sometimes described as a "wet dog", "burned", or "perm" smell. This particular smell of wet wool is present because we use natural merino wool that has been minimally processed in order to preserve the lanolin content inside the wool.
Lanolin is naturally present in merino wool and is responsible for giving wool all of the great properties that we love: wicks away sweat, resists stains, feels soft to the touch, stays elastic, and resists bacteria and odors. Wool is a natural product. Even if you have multiple products, one may have a higher lanolin content than the other, accounting for a difference in smell.
You should not notice this smell at all when the product is completely dry. Over time, the smell will be less and less noticeable after washing as the lanolin content in the wool dissipates.
How should I care for my Woolino sleep bag?
Merino wool by nature is self-cleaning and does not need to be washed as frequently as other fabrics. To refresh and reduce washing, air the garment often.
Machine wash: Close zipper. Wash on Low, 85°F /30°C max
Use wool or mild detergent.
Line-dry clothing and blankets. Sleep bags can be tumble dried on No Heat or Air Dry settings.
How to remove stains from wool?
Stains should be treated immediately. Do not apply any form of heat, as this tends to fix most stains making them more difficult to remove. Rinse the stain immediately and thoroughly in cold water. Then, apply one of these two homemade stain remover mixtures that we recommend:
The preferred option is a mixture of liquid laundry detergent and a few drops of white vinegar. Cover the stain with the mixture and allow the liquid to sit on the stain for at least an hour. Blot the stained area gently with a cloth before rinsing thoroughly with clean water. Repeat if necessary.
Another option is a mixture of one part (1 Tsp) dish soap and two parts (2 Tsp) Hydrogen Peroxide (3%). Apply some of the mixture over the stain and let it sit for several hours. Wash afterwards as usual.
When ready to wash, check the product care tag for best results. Following our recommended care instructions will ensure the best possible wear while maintaining & prolonging the life of your Woolino.
Here's a link to The Best Ways to Remove Stains from Your Wool Clothes provided by Woolmark. It contains a comprehensive list of different types of stains and a step-by-step guide for removal: https://www.woolmark.com/care/stain-removal-wool/
Please Contact Us and we'll answer your question promptly.
A study done by the University of Sydney has found that a better night's sleep is achieved when sleeping in wool.
Superfine merino wool is the perfect fiber to have next to your child's sensitive skin. It's cuddly soft and uniquely temperature regulating - a perfect micro-climate for better and longer sleep.
We have a very active two year old who moves a lot in his sleep and always kicks off any blanket then wakes up chilly and mad about it. So after toying with the idea of transitioning out of the sleep sack into a regular blanket we instead opted to just get the next size! Why fix what’s not broken! If you have a kid who wanders around or needs to walk to the bathroom this isn’t a great choice but he’s not that kind of kid. He stays in bed all night
We’ve used Woolino sleep sacks ever since we sleep trained our son over a year ago. It began as part of the routine to get his body and mind ready for sleep and now my son picks it up after bc bath when he’s ready to read books and “get cuddly wuddly.” (Also helps keep him in his crib as he thinks he can’t climb out with it on.) Thank you for adding the bigger size!!!
Woolino sleep sacks are the only sleep sacks my son has used since 4 months old. He is now a tall 3.5 and wearing the 4-6 year sack to stay cozy in all temperatures. I have given them as gifts to 6 expecting mothers!
My 4 year old loves his sleep sack and was outgrowing his old one. I am so glad I found this one as I was having a lot of trouble finding one his size as he’s older and also tall for his age. This one is so comfortable and my son is very happy to have room to stretch his legs. It’s wonderful quality, can only recommend!
Totally did not see that this glows in the dark. Washed it and cannot return it anymore. Kids do not need glow in the dark sleep sacks. This should not be something parents have to watch out for.
We love these sleep sacks, the fabric is so nice, and they've really held up for more than 12 months of regular use and frequent washing. We haven't used any other bands since discovering Woolino.
I purchased this for my almost 5-year old grandson to replace his extremely loved and used smaller size sleep sack. "Little Orange" (as his smaller size sack was dubbed) was the ULTIMATE security blanket. We couldn't go anywhere in the car without it, and it was an essential part of bedtime. It literally was worn out to tatters (after multiple mendings) before it needed to be replaced. His parents tried to substitute other products--without success. The quality, comfort and 'cozy factor' of Woolino is unmatched. The price is high but the value for the dollar makes it worth every penny!
We love woolino. We have been using them for 3 years now. They’re so soft and I have peace of mind knowing my child is never too cold or hot. Worth every penny!!
Great! Soft fabric and peace of mind knowing my son will not be too hot or too cold year round which is important with midwestern weather! From 1°F-100°F, i know his body temp will be regulated
Your Woolino sleep sacks have been worn by our grandson since his parents stopped swaddling him. I really appreciate that the appearance of the sleep sack is a solid clue that sleep time has arrived, either nap or bedtime. His younger brother is about to inherit his collection, which is why I ordered the larger version. Thanks for great products
Fantastic sleep sack and can’t wait to use it for my toddler when they grow into it. We have been using Woolino sleep sacks for the last year. My long and lean toddler has enough room in these amazing sleep sacks - unlike other brands. Just follow the directions and DO NOT put in the dryer, and you’ll get many months of use!
I wish I had bought this earlier! It is truely self-adjusted to room temperature, so no more kicking off blanket or sweating, and no more cold hand & feet for my daughter! And no more waking up in the middle of night to put blanket back on my daughter for me! I will definitely buy more for my coming baby.
This is the third Woolino I’ve bought for my son. I have the 2 months to 2 years (which my infant daughter now wears) the 2-4 years, and I was so excited to find out that Woolino now has 4-6 years. This is the best sleep sack and the only one you will ever need. I never had to worry about my son overheating. He loves his sleep sack too. Some may think a 4 year old doesn’t need a sleep sack, but he can’t kick it off like he does with a blanket so he stays comfy all night. I recommend Woolino to every parent and it is so worth the money.
I have 2 of these now and I had the smaller size when my daughter was younger. I dont know how people do kids bedtime without them. It’s like a wearable comfy wool blanket that won’t fall off.
Our last woolino had gone through 4 cousins. He still loved it, but it was getting worn out. We got the big kid size and he loves the planet design. He stays cozy and comfortable year round.
The first time you wash it it smells like a wet stinky farm animal until it's dry. The smell fades a lot with time or I would have returned it. We've been using woolinos for our kids since they were newborns, so we own about ten of them in the various sizes. This winter my two year old has been too cold in this sleep sack (69 degree F bedroom) so I've bought a different brand that's 2.5 TOG to keep him warmer.
I've purchased different sleep bags for my kids on and off for 5+ years. Historically they have been excellent and long-lasting quality. However, I recently purchased one blue sleep bag and one green sleep bag. Both size 4-6 and was let down. They arrived quickly, but both had a strange and strong odor when I opened the packages. Very unusual. I washed them and it didn't go away. I used to love Woolino products and often gifted them to others, but I don't think I will any longer. I am hesitant to reach out to customer service because in the past it has taken a lot of effort to reach someone. Very disappointed as this was such a reliable brand in the past.
This is my second purchase, first I got the 2mo-2year old 4season sleep sac (which I used up until the new one arrived for my 3year old who just about still fitted in) and this time the 4-6year old one. It's soft, comfortable and good quality and we, parents, don't worry about blankets coming off at night and it's quick to put on and take off! It may seem a bit pricey, but the care and materials that have been put into these pieces make it worth it!
Our 4 year old has loved his Woolino sleepsacks since he was little. So when we saw the now make the next size up, he was so excited. Best baby/toddler product ever!
Have ordered Woolino since child number 1 and reused them with child 2 and now 3! Child 2 loves it so much that we have just ordered for 4-6 years old. So worth it as quality is amazing and so cozy and has lasted for years now.
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