Royal Cousins Princess Beatrice, Princess Eugenie and Zara Tindall Coordinate in Pink and White for Garden Party

Pink and white were the colors of the day for Princess Beatrice, Princess Eugenie and Zara Tindall.

The royal cousins joined Prince William at a Buckingham Palace garden party on May 21, and while the men (including Zara's brother, Peter Phillips, and husband, Mike Tindall) looked handsome in top hats and suits, the women popped in complementary ensembles.

Princess Beatrice, 35, looked ready for spring despite the rainy weather in a bold pink dress with long sleeves and a white hat. Her younger sister, Princess Eugenie, 34, opted for a white dress with a pale pink headpiece.

Their cousin Zara, 43, also stuck to the color scheme, sporting a white dress with pink buttons. She accessorized with a pink hat and heels.

The rain called for another matching accessory for all three women: black umbrellas!

Members of the British royal family are known to coordinate their outfits for events. At Trooping the Colour in 2022, the monarch's annual birthday celebration, Queen Elizabeth, Kate Middleton, the future Queen Camilla and others opted for blue ensembles.

Karen Haller, behavioral color psychologist and The Little Book of Color author, previously spoke to MyLondon about the royal family's habit of complementing each other in blue, noting it shows that "they are coming together as a family, representing themselves as a cohesive unit."

"When it comes to color psychology, darker blues communicate you are in a position of authority, trustworthy, reliable and can be depended on," she added. "You have a sense of duty and take that seriously with committed focus."

Queen Elizabeth's trusted aide and friend Angela Kelly wrote about how the royal family approaches colors in her book, The Other Side Of The Coin: The Queen, the Dresser and the Wardrobe. Kelly said that when the monarch, who died in Sept. 2022, needed an evening dress, she would lay out sketches for the Queen to pick from.

"Once Her Majesty has chosen her dress for dinner, a handwritten notice is pinned up in the Dressers' Corridor detailing what she will be wearing, so that The Queen's ladies' maids can select an appropriate dress for the lady they are looking after," she wrote. "When it comes to the Royal Family, it doesn't matter if they wear the same colour as The Queen because they are family, and sometimes the ladies will wear cocktail dresses even though The Queen might be wearing a long one."

She continued, "Other guests, though, feel they shouldn't be in the same colour as Her Majesty, although The Queen would not mind if this did happen."

Queen Elizabeth also gave careful thought to the shade of her outfits, usually wearing bright colors for royal engagements to stand out in a crowd.

In the documentary The Queen at 90, the Queen's daughter-in-law Sophie, the Duchess of Edinburgh said: "She needs to stand out for people to be able to say 'I saw the Queen.' Don't forget that when she turns up somewhere, the crowds are two, three, four, 10, 15 deep, and someone wants to be able to say they saw a bit of the Queen's hat as she went past."

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It was a rare occurrence for five of Queen Elizabeth's eight grandchildren to get together for a royal event. Although they are spotted together at family events such as Christmas, most of the cousins are not working members of the royal family, instead holding jobs while also supporting charitable causes. Not in attendance at the garden party were their two youngest cousins, 20-year-old Lady Louise, who is studying at the University of St. Andrews, and 16-year-old James, Earl of Wessex. Prince Harry, who relocated to California in 2020 with Meghan Markle after stepping back as working members of the royal family, also was not present.

While King Charles and Queen Camilla hosted two garden parties earlier this month, Prince William stepped in for his father on May 21. There, he mingled with some of the thousands of guests at the event, who were invited in recognition of their public service. Among the attendees were guests from both Prince William and his wife Kate Middleton's patronages, military affiliations and passion projects.