Prince William Teams Up with His Royal Cousins to Host a Rainy Buckingham Palace Garden Party

It's a royal cousin outing as garden party season is in full swing!

Prince William looked dapper in a morning suit and top hat as he stepped in to host a garden party at Buckingham Palace on May 21 on behalf of his father, King Charles. While his wife, Kate Middleton, continues to stay out of the public eye as she undergoes cancer treatment, the Prince of Wales, 41, invited some of his cousins to help with hosting duties at the afternoon festivities.

Princess Beatrice, Princess Eugenie, Peter Phillips, Zara Tindall and her husband, Mike Tindall, joined Prince William in a rare outing highlighting the next generation of the royal family. Beatrice, 35, Eugenie, 34, and Zara, 43, coordinated in pink and white ensembles, while Peter, 46, and Mike, 45, rocked top hats with their suits.

While Queen Elizabeth's grandchildren are often seen together at family events such as Christmas, they 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.

The Duke of Gloucester, Queen Elizabeth's first cousin, and his wife, the Duchess of Gloucester, also attended the garden party.

The royals mingled with the thousands of guests at the event, who were invited to the royal residence in recognition of their public service. Among the attendees were guests from both Prince William and Princess Kate's patronages, military affiliations and passion projects including Homewards, RAF Valley, Swim England and tenants across Duchy of Cornwall sites.

Proving that garden parties are "rain or shine" outdoor gatherings, the royal family members and guests carried umbrellas due to rain. (Queen Elizabeth admitted in 2019 that the weather "can be a bit of a worry," adding, "Well, you do rather hope the sun shines as when you invite 8,000 people to have tea on your lawn.")

King Charles and Queen Camilla hosted the first garden party of the year on May 8, with Princess Anne, Prince Edward, Sophie, the Duchess of Edinburgh and the Duke and Duchess of Gloucester also in attendance. The outing coincided with Prince Harry's attendance at the Invictus Games anniversary service at St. Paul's Cathedral in London. It was revealed ahead of the visit to the U.K. that the Duke of Sussex would not be able to meet with his father due to the monarch's "full" schedule.

The King, 75, and Queen, 76, stepped out for another garden party on May 15, hosting the Sovereign's Creative Industries Garden Party at Buckingham Palace.

Princess Anne then played host for the Not Forgotten Association Annual Garden Party at Buckingham Palace on May 17. The Not Forgotten Association is a charity that provides entertainment, leisure and recreation for the serving wounded, injured or sick and for ex-servicemen and women with disabilities.

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Garden parties have been held since the 1860s as a way for the monarch to recognize community members for their public service. As the weather warms up, the sovereign traditionally hosts several of the outdoor events at Buckingham Palace and one at the Palace of Holyroodhouse in Scotland. Over 30,000 guests each year are invited to spend the afternoon in the picturesque gardens of the royal residences.

In addition to mingling with members of the royal family and strolling around the palace grounds, guests are treated to tea and cake. (The royals' website previously stated around 27,000 cups of tea are served and 20,000 slices of cakes are consumed!)