Why Kate Middleton's royal tour wardrobe is causing controversy.

Kate Middleton has found herself surrounded by controversy… and it’s all due to a hat.

During the recent Royal tour of Scandinavia, the Duchess of Cambridge wore a woolly hat with a fluffy pom pom on top to an icy hockey match.

As is customary with anything she wears, fans quickly identified where and what she was wearing. It was then that some noticed a detail they weren’t impressed with.

The hat was identified as the Rain wool hand-knit beanie in charcoal, $360, by New York designer Eugenia Kim. The product details on the website were promptly updated with the photo of the Duchess wearing the item as well as the phrase, "Worn by Duchess of Cambridge Kate Middleton on the 2018 Royal Tour to Sweden".

The problem? The pom pom at the top is made from arctic fox.

Kate Middleton was pictured in Stockholm in what appeared to be a Harvey Nichols hat with a bobble with 100% arctic fox fur. KP now SAYS the bobble was faux fur, BUT here is the real fox fur hat side-side with Kate’s, it appears KensingtonPalace lied.???? https://t.co/lNxIOw3JQk pic.twitter.com/5dhpjTvK5y

— Royally_Petite (@RoyallyPetite) January 30, 2018

Another Twitter user described it as "disgusting and inexcusable".

Kensington Palace were forced to issue a statement insisting the hat was made from faux fur.

"In spite of the Twitter outcry, Kensington Palace says the Duchess was not wearing fur on her bobble hat earlier. I believe the gloves are fake fur too and the coat shearling," tweeted Richard Palmer, royal correspondent of the Daily Express.

"Kensington Palace has double checked and is adamant the hat is faux. It won't confirm the make. Is this #fakefurnews?" (Post continues after gallery.)

Other users pointed out that the product description on Kim's website includes a note that says "this style is also available to be made to order with a faux-fur pom".

It's not the only item in the Duchess' wardrobe causing confusion.

She was also pictured sitting inside with the Norwegian Royals... with her coat on.

As the parents around the world would say, "Was she not staying?"

According to OK! magazine, it's got nothing to do with the temperature or dissatisfaction with the company. Rather, it's royal protocol.

It's considered ‘unladylike to undress in public’, and in this case "undressing" involves removing your coat.

The more you know.