Significance of Prince William and Kate Middleton's blue clothing in 'emotional' video after fans spot key detail

Since the release of the touching video in which Kate Middleton reveals she has finally finished her chemotherapy treatment, people have spotted one key detail.

The video, which was posted yesterday on their Kensington Royal official X account, it shows the family walking through the woods while Kate talks about starting a new chapter of life.

Speaking about her cancer journey over images showing the Wales' and their children, Kate says: “As the summer comes to an end, I cannot tell you what a relief it is to have finally completed my chemotherapy treatment.

“The last nine months have been incredibly tough for us as a family. Life as you know it can change in an instant, and we’ve had to find a way to navigate the stormy waters and road unknown.”

She added: "Doing what I can to stay cancer-free is now my focus. Although I have finished chemotherapy, my path to healing and full recovery is long and I must continue to take each day as it comes."

She continued: "I am, however, looking forward to being back at work and undertaking a few more public engagements in the coming months when I can.

"Despite all that has gone before, I enter this new phase of recovery with a renewed sense of hope and appreciation of life."

But a lot of people clocked the same thing, that everyone in the video was wearing blue. In fact, the family always seem to wear blue.

The touching video showed Kate Middleton and Prince William ejoying time together with their children (X/@KensingtonRoyal)

After watching the wonderful video, someone shared with online fans: “On a lighter note, I appreciate this family's commitment to dressing in blue.”

Someone commented below: “Cambridge Blue FOREVER.”

But why do they wear blue?

According to Elizabeth Holmes, author of New York Times bestseller, HRH: So Many Thoughts on Royal Style, it’s on purpose.

She told Vogue: “The royal family is always very aware of the message their clothing sends. A huge part of their very public role is to be seen– as Queen Elizabeth II famously said.

“Before anyone knows what work they are doing, what cause they are supporting, or what event they are attending, we see what they are wearing. They know that and they use that quite savvily.”

Fans have been quick to point out how the family always seem to be wearing blue (X/@KensingtonRoyal)

But what draws them to blue, and not other colours?

According to the publication, the colour is all about projecting calmness and her responsibility. Or, it could be a nod to the Union Jack, as wearing blue subtly hints to the nation.

Holmes also explains that for Middleton, blue is her signature look.

She explained: “I think it’s worth considering Catherine’s commitment to blue. For the first official pictures of her as a royal bride-to-be, she wore a vivid blue wrap dress to match the famous sapphire and diamond engagement ring that had belonged to Princess Diana.

"She has since worn every shade of blue, from a soft and pale (one might even call it Cinderella blue) to a deep navy.”