Kate Middleton, Meghan Markle
Kate Middleton and Meghan Markle always wear blue in public. Pictured: Middleton, Markle attend day twelve of the Wimbledon Lawn Tennis Championships at All England Lawn Tennis and Croquet Club on July 14, 2018 in London, England. Getty Images/Clive Mason

Meghan Markle and Kate Middleton always wear blue in public due to an important reason.

Karen Haller, an applied color psychology specialist, told Daily Mail that the Duchesses may have been deliberately choosing the color because blue communicates professionalism.

“When it comes to the psychology of color, blue relates to the mind. Darker blues relate to trust, logic, and knowledge. It communicates duty and professionalism and given it’s a more approachable color than black, maybe why she wore this hue often on her recent 16-day royal tour down under,” she said.

“Subconsciously, wearing darker blues might suggest that – this being her first major royal tour – she wanted to maintain her focus and concentration during her royal duties,” Haller added.

Kathryn Knight, a journalist for Express, noted the fact that Markle wore eight navy blue outfits during her 16-day tour of Australia, Fiji, the Kingdom of Tonga, and New Zealand with Prince Harry. Last month, Markle also sported a navy blue Givenchy coat dress when she attended Princess Eugenie and Jack Brooksbank’s wedding.

Middleton, on the other hand, was photographed in her blue attire two times this week. When she visited McLaren’s Automotive Center with Prince William, the Duchess of Cambridge was seen in her recycled navy blue Eponine coat dress. When the mom of three went to the Imperial War Museum, she was seen in her blue Jenny Packham attire.

In related news, Middleton and Markle went on a double date with their respective husbands on Thursday evening. The two couples graced a Royal Foundation Dinner at the Victoria House in London and were joined by British singer Tom Walker.

The royal couples’ reunion came one day after they all attended Prince Charles 70th birthday party at the Buckingham Palace, which was organized by Queen Elizabeth II.

“How am I feeling? Older, older. I’m not sure, it’s rather like indigestion, many happy returns are not quite the same thing as you get older,” Prince Charles said when the press asked him how he felt on his special day (via E! News).