The Royal Ascot is still a family affair for Prince William.

As Kate Middleton continues to seek preventative chemotherapy treatment, her parents Carole Middleton and Michael Middleton joined the Prince of Wales at the annual horse racing event on June 19.

Per tradition, William wore a top hat and a three-piece suit, which he paired with a blue patterned tie and a purple boutonniere. Keeping with the floral theme, Carole donned a light blue dress adorned with periwinkles and a matching fascinator, while her husband opted for the conventional waistcoat as well as striped trousers and a black hat.

At one point during the day, William, 41, sweetly held his mother-in-law's hand as he led her across the green lawn. He was also seen chatting with cousins Princess Beatrice, Princess Eugenie and Zara Tindall.

The outing came less than a week after Kate, 42, made her first public appearance since sharing her cancer diagnosis in March. At the Trooping the Colours ceremony on June 15, the Princess of Wales—clad in a black-and-white Jenny Packham dress paired with a Philip Treacy hat—accompanied William and their kids Prince George, 10, Princess Charlotte, 9, and Prince Louis, 6, on the Buckingham Palace balcony to watch the Royal Air Force flypast.

According to the royal, she has been "making good progress" on her treatments, though "there are good days and bad days."

"On those bad days you feel weak, tired and you have to give in to your body resting," Kate wrote on Instagram June 14. "But on the good days, when you feel stronger, you want to make the most of feeling well."

She continued, "My treatment is ongoing and will be for a few more months. On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home."

Kate, who was diagnosed with an unspecified form of cancer after undergoing abdominal surgery in January, added that she has been "blown away by all the kind messages of support and encouragement over the last couple of months."

"It really has made the world of difference to William and me," she wrote, "and has helped us both through some of the harder times."

To see the princess at the Trooping the Colours ceremony, keep reading.

Kate Middleton smiled as she appears with the royal family at Trooping the Colour, an annual ceremonial military event celebrating King Charles III's birthday. It marked the Princess of Wales' first public royal engagement since December 2023, and her first major appearance since revealing her cancer diagnosis in March 2024.

The Wales family waved at the crowd from a Buckingham Palace balcony.

Prince George, 10, and Prince Louis, 6, had a chat.

Prince William and Kate Middleton shared a sweet moment.

Prince William and Kate Middleton appear on the Buckingham Palace balcony with kids Prince George, 10, Princess Charlotte, 9, and Prince Louis, 6.

Kate Middleton, Prince William, Prince George, Prince Louis and Princess Charlotte are seen arriving at Trooping the Colour.

King Charles III was accompanied in a carriage by his wife, Queen Camilla. 

Kate and her kids are seen inside their carriage.

Prince George and Princess Charlotte waved to royal fans on the ride.

Prince Louis was spotted in his signature style.

The Princess of Wales, who's been undergoing a course of preventative chemotherapy, sat beside her youngest child during their carriage ride.

Prince William was joined by Princess Anne and Prince Edward as they rode on horseback.

The Princess of Wales arrives at her first formal appearance in six months. Kate appeared at the Trooping the Colour parade two months after revealing she is undergoing cancer treatment.

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