Please find below answers to most of the frequently asked questions we receive. Should you not find the answer you are looking for please contact us and it will be a pleasure to inform you.

Using a baby sleep bag ensures your baby’s temperature stays constant, avoids baby’s restlessness (constant waking at night) and swaddling too tightly.

A baby sleep sack is a safer alternative to loose sheets and blankets. The sleep bag also becomes a positive sleep association for babies that will signal sleep.

A baby sleeping bag is probably the most important piece of clothing for your baby since babies sleep 14 to 17 hours a day on average.

It makes it a sound investment in your child’s wellbeing. The sleep sack is also potentially reducing the chances of Sudden Infant Death Syndrome (SIDS) and also helps in the prevention of Development Dysplasia of the Hip (DDH) since it is loose-fitted from the hips down.

Research has shown that among the benefits of using a safe baby sleeping bag (a safe baby sleeping bag has fitted neck, armholes, no hood and is the correct size for baby) are:

  • they reduce the risk of bed clothes covering baby’s face
  • they delay baby rolling onto the tummy during sleep until baby’s past the age of peak of SUDI (Sudden Unexpected Death in Infancy)
  • they promote back sleeping as the zipper opens to the front
  • they will keep baby’s temperature at a more constant level while sleeping

Source: https://rednose.com.au/article/benefits-of-using-a-safe-baby-sleeping-bag

Research has found that children’s sleep bags may have a protective effect against SIDS, since they reduce the incidence of turning to a prone position and prevent bedding from coming up over the face and the head during sleep.

Source: European Commission Recommendation for Sleep Environment

Baby sleeping bags create a positive sleep association for babies which is comforting to them. It is a great addition to the bedtime routine, creating a smoother sleep ritual.

Australian merino wool is the world’s finest and softest wool in the world.

In a nutshell, the key benefits of merino wool which make it ideal for a baby sleeping bag are:

  • 100% natural
  • eco-friendly
  • lightweight
  • biodegradable and renewable
  • naturally antibacterial & hypoallergenic
  • moisture-wicking and breathable
  • helps regulate body temperature
  • skin friendly: soft and good for sensitive skin
  • helps with eczema and asthma
  • highly durable
  • fire resistant and natural fire retardant
  • protects against UV radiation
  • allergy-safe
  • machine washable

The Woolmark Company made a comprehensive video explaining the key benefits of merino wool that you can watch by clicking here.

The unrivalled benefits of 100% merino wool and the modern design, incorporating the highest level of flexibility and functionality, provide maximum comfort for your baby over the crucial first two years.

Our organic baby sleep sack is made to last: to be worn from the age of 2 months to 24 months + and for all 4 seasons which makes it a sound investment in your baby’s wellbeing. Merino wool is also durable and eco-friendly: you do not need to wash it often and you do it dries quickly.

Merino wool is one of the most comfortable fibres for luxury next-to-skin garments. We only use 100% Australian merino of 17.9 microns (qualified as Extra Fine by Woolmark), meaning extremely high quality. We use two layers of this amazing wool, ensuring all the goodness from the merino wool fibre is kept and not tainted by another fabric. Our merino wool is ethical, certified and extremely soft. We also do not chemically treat our garments with nasty chemicals in any way during or after the manufacturing process, keeping them pure and safe.

Our award-winning product is made by business partners who take quality and health seriously. Our partners have the following internationally renowned certifications: Merino ZQ from our merino wool sourcing partner (Südwolle Group from Germany), OEKO-TEX 100 Class I for babies meaning that our fabric and trimmings contain no harmful substances, certification and inspection from Business Social Compliance Initiative (BSCI), Deloitte certificate confirming no mulesing of sheep and the prestigious Woolmark’s Nurture certification which applies only to the finest Woolmark-certified materials. Our merino wool baby sleeping bag is the only sleep sack that has received this acclaimed Woolmark certification.

Furthermore our merino baby sleeping bag contains no endocrine disrupting chemicals: pesticides are not used during the production of merino wool (heavily used for cotton and sometimes finished cotton garments have some particles left), we do not use polyester filling/wadding aka plastic (like most sleeping bags that have a TOG), no fire retardant is used during and after manufacturing (some synthetic baby sleeping bags have them added) and all our trimmings (zipper, snap buttons) are nickel-free.

Merino wool is also skin friendly: it is antibacterial and hypoallergenic which allows the skin to breathe naturally, which reduces sweating and absorbs moisture, reducing skin irritations, allergies, asthma and eczema. Merino wool is the best next-to-skin garment for your baby’s sensitive skin.

Our baby sleeping bags are conform to UK BS 8510:2009 and AS/NZS 1249:2003 standards for kids’ sleepwear safety.

The MookieMerino 4-Season Sleep Bag won the following awards so far:

  • Australian Non-Toxic Awards 2020
    • Silver / Baby Sleeping Bag
  • Parent & Baby Awards 2020
    • Best Premium Unisex Baby Sleeping Bags Range – UK
  • National Parenting Product Awards 2020
    • Bronze / Best Baby Sleepwear Product
  • Junior Design Awards 2019
    • Bronze / Best Sleepwear Collection (Baby Sleeping Bag)
  • Eco-Excellence Awards 2018
    • Best Baby Gear (Swaddles)
  • Parent & Baby Awards 2018
    • Best Baby Sleep Clothing Product
  • Woolmark’s Nurture certification which applies only to the finest Woolmark-certified materials;
  • OEKO-TEX Standard 100 Class I for babies for our merino wool and all trimmings (snap buttons, zipper, etc) meaning they contain no harmful substances (same as the European REACH standards). Our trimmings are also nickel-free;
  • Business Social Compliance Initiative (BSCI) which states that our factory meets global standards;
  • Deloitte certificate confirming no mulesing of sheep;
  • Conforms to UK BS 8510:2009 and AS/NZS 1249:2003 specifically for child’s sleepwear safety.

Furthermore our merino baby sleeping bag does not contain endocrine disrupting chemicals: free of pesticides (heavily used for cotton production), polyester filling (aka plastic), fire retardants chemicals and nickel.

Have you heard of EDCs (Endocrine-disrupting chemicals)? Common EDCs used for children’s products are Lead, Phthalates, Cadmium and Certain Plastic.

Endocrine-disrupting chemicals (EDCs) are substances in the environment (air, soil, or water supply), food sources, personal care products, and manufactured products that interfere with the normal function of your body’s endocrine system (network of glands and organs that produce, store, and secrete hormones).

The merino wool and trimmings used for the MookieMerino 4-Season Sleep Bag are OEKO-TEX certified meaning they do no contain nasty chemicals.

Our merino wool baby sleeping bags are free of pesticides (heavily used for the production of cotton), polyester fillings (polyester is made from plastic fibres), fire retardants chemicals and nickel (our zippers and snap buttons are certified nickel-free).

For more information on EDCs:




The Woolmark Nurture certification applies only to the finest Woolmark-certified materials. It is a symbol of quality assurance, proving fibre content and fitness for purpose through strict testing, which follows global industry standard.

The diameter of the merino wool fibre in certified Woolmark Nurture products has an upper limit for each product category to ensure the products are comfortable for babies. For instance, the MookieMerino 4-Season Sleep Bag Merino is guaranteed to be made from merino wool with a micron of 17.9 (this has been confirmed through testing), no wonder it feels luxuriously soft against a baby’s skin.

The STANDARD 100 by OEKO-TEX® is a worldwide consistent, independent testing and certification system for raw, semi-finished, and finished textile products at all processing levels, as well as accessory materials used.

What does OEKO-TEX Standard 100 takes account of?

  • Important legal regulations, such as banned Azo colourants, formaldehyde, pentachlorophenol, cadmium, nickel, etc.
  • Numerous harmful chemicals, even if they are not yet legally regulated.
  • Requirements of Annexes XVII and XIV of the European Chemicals Regulation REACH as well as of the ECHA SVHC Candidate List insofar as they are assessed by expert groups of the OEKO-TEX® Association to be relevant for fabrics, textiles, garments or accessories.
  • Requirements from the US Consumer Product Safety Improvement Act (CPSIA) regarding lead.
  • Numerous also environmentally relevant substance classes

What is OEKO-TEX Standard 100 class I?

Articles for babies and toddlers up to 3 years of age (underwear, rompers, clothing, bed linen, terry products etc.). This category is the strictest because of the product direct contact to a sensitive skin.

What is the importance of OEKO-TEX?

With its decades of experience, the OEKO-TEX® Standard 100 therefore contributes to high and effective product safety from a consumer’s point of view. Test criteria and limit values in many cases go far beyond applicable national and international standards. Extensive product checks and regular company on-site visits also ensure that the industry has a globally sustainable awareness of the responsible use of chemicals.

Source: https://www.oeko-tex.com/en/business/business_home/business_home.xhtml

The European Union has restricted a great number of chemicals in products that are marketed in Europe to ensure product safety. Textile chemicals are regulated under the REACH legislative framework, specifically Annex XVII. REACH stands for the Registration, Evaluation, Authorisation and Restriction of Chemicals.

The Annex XVII of REACH restrict the usage of a long list of nasty chemicals in clothing, including:

  • Azodyes
  • Metal (including nickel)
  • Phthalates
  • Flame retardants
  • Formaldehyde
  • Cadmium
  • Organotins
  • PAHs

Sources: https://www.cbi.eu/market-information/apparel/buyer-requirements/




Baby sleep bags are a popular alternative to blankets and sheets and remove the need for additional bedding when sleeping in a cot or similar product. They were introduced in an effort to reduce the incidence of Sudden Infant Death Syndrome, known as Cot Death in the UK. They are designed to keep children of 4kg or more at a comfortable temperature through the nights and, as opposed to adult sleeping bags, they are intended for indoor use.

Baby sleep bags marketing in the UK must meet the requirements of BS 8510:2009 which include specifications on:

  • Chemical Hazards
  • Thermal Hazards
  • Mechanical hazards such as entrapment, entanglement, chocking and ingestion, suffocation, structural integrity
  • Thermal resistance (TOG)
  • Flammability

Sources: https://www.bureauveritas.co.uk/services+sheet/baby+sleep+bag

The AS/NZS 1249:2003 standard is used in Australia and New Zealand for children’s nightwear relating to their risk as fire hazard. The standard includes:

  • Mechanical hazards including dimensional requirements for the trims, attachments, slits and fastenings
  • Flammability and its labelling requirement categorised by the type of fabric

Source: https://archive.org/details/as-nzs.1249.2003/page/n19

The Business Social Compliance Initiative (BSCI) is a leading supply chain management system that supports companies to drive social compliance and improvements within the factories and farms in their global supply chains.

BSCI implements the principle international labour standards protecting workers’ rights such as International Labor Organization (ILO) conventions and declarations, the United Nations (UN) Guiding Principles on Business and Human Rights and guidelines for multinational enterprises of the Organization for Economic Co-operation and Development (OECD).

Source: https://www.amfori.org/content/what-we-do-0

The sudden unexpected death of a baby, when there is no apparent cause of death, is now called Sudden Unexpected Death in Infancy (SUDI). This includes Sudden Infant Death Syndrome (SIDS) and fatal sleep accidents. A baby can be the victim of SUDI at any time of the day or night, but it is usually during their sleep. SIDS used to be called ‘Cot Death’.

Source: https://www.betterhealth.vic.gov.au/health/healthyliving/sudden-unexpected-death-in-infants-sudi-and-sids

The recommended room temperature whilst your baby is asleep is between 16 and 20 degrees Celsius (61 and 68° degrees Fahrenheit).

The law obliges us to indicate a room temperature range on our packaging and product. However, as the MookieMerino 4-Season Sleep Bag is made of 100% merino wool, its climate management capabilities makes it ideal for any room temperature and thus the TOG (thermal insulation guideline) is irrelevant for this natural fibre.

Merino sheep living in Australia are used to extreme temperatures, hot during the day and cold at night, which is why merino wool adapts to temperature changes so well. Merino wool keeps you cool when it’s hot and warm when it’s cold.

Our merino wool sleeping bag is therefore perfect for normal room temperatures which makes it ideal for all 4 seasons.

To check your baby’s temperature it is recommended that you put your hand on its back or chest, as these are the spots which give you the best indication of your baby’s true temperature. It is normal that hands and arms seem colder.


  • Please note this sleep bag is made for indoor use – in a cot or a crib – in a room between 16 and 20 degrees Celsius. Can also be used in a pram/stroller and car seat thanks to its 5-point harness travel slot to fasten a seat belt;
  • Do not use the sleep bag if the child’s head can pass through the neck-hole – or the neck hole is too tight – when the product is fastened for use. Do not use if the baby weighs less than 4 kilograms;
  • Do not use the sleep bag if the fastenings are damaged;
  • Keep away from fire and flame;
  • Do not use with a quilt, blanket or other warm items to avoid overheating.

Our MookieMerino 4-Season Sleep Bag can be used all year round.

Baby can only wear a nappy when in the sleep bag. However if you feel you have to layer while using the sleeping bag, we recommend adding a thin long sleeve top (ideally made from natural fibre) when the room is colder.

Obviously every child is different, some feel cold more easily than others for example, so we strongly recommend you touch your child’s skin (either on their back or on their chest/tummy) to gauge your Mookie’s real body’s temperature and layer appropriately. Your baby’s hands and feet are not good indications of their actual body temperature because of the immaturity of the circulatory system.

Merino wool is lighter than traditional wool and synthetic fabrics. Most sleep bags on the market are thicker because they use synthetic materials like polyester filler which is a heavier material.

Don’t be fooled by its appearance, merino wool keeps your baby warm in winter and cool in summer.

Sheep go through extreme temperatures in the wild in Australia, from hot days to cold nights and their wool has adapted to these conditions.

Merino wool naturally assists in regulating the body’s temperature in all weather conditions, making it one of the most breathable fabrics. Merino fibres can absorb large quantities of moisture vapour then move it away from the body so it evaporates into the air.

Scientific studies have showed that wool sleeping apparel and bedding increases total sleep time, promotes sleep onset and improves sleep efficiency.

TOG gives an idea of the thermal resistance, meaning how warm an item is (the higher the TOG, the warmer the sleeping bag). The TOG indicates, approximately, how many blankets the sleeping bag is equivalent.

To conform to the British Safety Standard for baby sleep bags, a TOG rating must be stated on our sleep bags but it is actually not accurate since our sleep bag is made of 100% merino wool and this natural fibre adjusts according to the temperature.

Indeed TOG doesn’t really apply to merino wool due to its amazing thermo regulation capacity, which helps in naturally regulating baby’s body temperature, keeping baby warm in winter and cool in summer.

The MookieMerino 4-Season Sleep Bag is a modern baby sleeping bag. You do not need to scratch your head wondering which TOG is appropriate to use and waste money on buying many sleeping bags with different TOGs depending on the time of the year. Our baby sleep sack is not only suitable for all 4 seasons but is adjustable so it can grow with your baby to at least the age of two. It is your complete baby sleeping garment.

Our sleep bag is sleeveless to ensure there is adequate air circulation around the baby’s body, which prevents overheating. The sleeveless style is also a requirement to be compliant with safety standards associated with kids’ sleepwear.

As a comparison, babies that sleep with traditional sheets and blankets rarely sleep with their arms underneath the sheets/blankets.

If your baby’s arms seem cold, we recommend adding an additional light layer to the baby’s upper body under the sleep bag. To check the baby’s body temperature, place your hand behind its neck or on the chest/tummy to assess the real body temperature.

You can wash the MookieMerino 4-Season Sleep Bag in the washing machine inside out at a gentle cycle (maximum 40 degrees Celsius) using a wool-approved detergent. Do not bleach and do not tumble dry.

Please allow for up to 5% shrinkage after repeated washing. Light pilling is also normal for merino wool.

Merino sheep were first bred in Spain where they became prized for their fine wool. It was in 1797, towards the beginning of European settlement, that the breed was introduced into Australia.

It was in Australia that the merino sheep, through selective breeding, developed even finer fibre as early farmers succeeded in producing the first authentic Australian merino wool.

The secret to merino wool’s success lies in its exceptionally fine fibres, which make it the softest wool available. Being so extremely fine, they are able to bend far more than other coarser wool fibres. It also has higher elasticity that helps prevent garments made with merino wool from losing their shape.

Merino wool is made out of keratin, much like human hair, meaning it is completely biodegradable. When it is eventually disposed of, it will breakdown, decomposing to release vital nutrients back into the soil, acting like a fertiliser.

Source: http://merino.com/wool/the-fibre/merino-wool-explained/

Merino fibres are extremely fine, enabling them to bend far more than traditional, coarser wool fibres. This makes merino wool feel soft and luxuriously gentle next to your skin.


In contrast to synthetics, merino is an active fibre that reacts to changes in body temperature. So it helps you stay warm when the weather is cold, and cool when the weather is hot. In contrast to synthetics, merino wool can absorb moisture vapour which means less sweat on your body.


Bamboo has many benefits in itself, unfortunately it is now becoming a big industry (there are claims producers are now using pesticides to increase their yield) and a great deal of its natural goodness is lost in the manufacturing process which relies on chemicals.


Natural fibres have their problems too. Cotton is the most pesticides intensive crop in the world: these pesticides injure and kill many people every year. Herbicides, and also the chemical defoliants which are sometimes used to aid mechanical cotton harvesting, add to the toll on both the environment and human health. These chemicals typically remain in the fabric after finishing, and are released during the lifetime of the garments. The development of genetically modified cotton adds environmental problems at another level.

Cotton is one of the most chemically dependent crops in the world. While only 2.4 percent of the world’s cropland is planted with cotton, it consumes 10 percent of all agricultural chemicals and 25 percent of insecticides. Some genetically modified varieties, which are resistant to some insects and tolerant of some herbicides, now make up more than 20 percent of the world’s cotton crop.

Even organic cotton uses excessive amount of resources to produce: while cotton, especially organic cotton, might seem like a smart choice, it can still take more than 5,000 gallons of water to manufacture just a T-shirt and a pair of jeans.

It can take more than 20,000 litres of water to produce 1kg of cotton; equivalent to a single T-shirt and pair of jeans.







Definitely! It is the best fibre for people affected by eczema and other skin conditions. Research has shown that wearing superfine Merino wool significantly improves the severity and symptoms of this chronic skin condition.

Studies have found that whether it’s hot, cold, humid or dry, garments made from merino wool are the most breathable compared with garments made from most common apparel fibre types. Wool can absorb and release twice as much moisture vapour as cotton and 30 times as much as polyester.

When worn next to the skin, wool works to buffer the dynamic micro-climate between the fabric and the skin, helping to stabilise the humidity and temperature. It appears that wool acts like a second skin.

Eczema affects up to 28% of infants with increasing prevalence in many parts of the world.

Source: https://www.woolmark.com/globalassets/02-about-wool/factsheets/gd2405-wool-is-good-for-skin_15.pdf

Absolutely not. Extra Fine quality merino wool – like ours at 17.9 microns, which is rarely seen on the market – is extremely soft on a baby’s delicate skin. Merino wool is actually recommended for babies since it helps treat skin conditions like eczema.

Baby sleep bag, baby sleeping bag, baby sleeping sack, baby sleep sack, baby bag sleepers, sack sleepers and wearable blanket are all synonyms.

Your baby’s sleep (and yours) is of the upmost importance, hence why we created our infant sleeping bag in the first place.

We have a baby sleeping tips section on this website for general advice, click here to be redirected. It includes sleep medical research findings on the benefits of merino wool for a better sleep.

We are a European brand and we ship globally. All our parcels are tracked.

We offer FREE deliveries within the UK, a flat rate of £9.99 (or equivalent in your currency) for Europe and a flat rate of £14.99 (or equivalent in your currency) for international orders.

For more information please refer to our delivery page by clicking here.

We offer quick and easy returns/refunds within 14 calendar days from when you received your order.

For more information please click here.

General Customs/Duties

When your items are delivered, you may be liable for customs duties and/or additional taxes depending on where you live. These customs and import regulations vary greatly from one country to another and we regret that we cannot take responsibility for these as they are outside our control.


Since the United Kingdom is no longer a member of the European Union, parcels (currently all sent from our warehouse in the UK) sent to EU countries are likely to be charged VAT and/or other charges and will be treated like any parcel coming from non EU countries like the USA, China, etc. The only exception to this rule is Ireland as they also charge 0% VAT on children’s clothes.

If you live in the EU (at the exception of Ireland) you should receive a notice advising you of the extra cost to be paid before your parcel is delivered to you. These extra charges are unfortunately out of our control and we thank you for your ongoing support.

We currently accept PayPal, Stripe (Bancontact, EPS, Giropay, iDEAL, Multibanco, Przelewy24, SOFORT and China UnionPay), MasterCard, Visa, Discover and American Express.

All payments are made through PayPal or Stripe which are the safest and most secure ways to make payments online.

You do not need a PayPal or Stripe account to make a payment: you can use your credit card through their secure platforms. You may also be eligible for PayPal Buyer Protection.

Our website is protected by McAfee SECURE / Trusted Site and SSL encryption with Let’s Encrypt.

The company’s head office is located in Malta since the founder, a Canadian and Australian citizen, used lived there for a decade. At the end of 2020 she relocated to Singapore.

Malta, located in the Mediterranean, is part of the European Union so the company strictly adheres to its customer protection laws and any other obligations originating from being part of the EU.

We respect your privacy and won’t pass on your details to any third party. We don’t like spam or unsolicited mail either. Your information is only stored in our systems in order to service you. For more information on our privacy policy please click here.

Information on this website, for the “sleeping tips” section for example, has been taken from reliable sources, however we cannot be held responsible for errors.

If you are unsure about any information on this website please do not hesitate to seek professional advice as no information on this website supersedes professional advice.

MookieMerino is protected by trademark, any reproduction of the product, name or logo – even partial – is forbidden.