Princess Kate, the Princess of Wales, has written a heartfelt letter to the Irish Guards, apologizing for her absence at the final rehearsal for the Trooping the Colour parade, which is set to honor King Charles III's birthday on June 15. The princess, who is currently undergoing treatment for cancer, expressed her pride in the regiment and wished them good luck as they prepare for the annual military parade.

In the letter, shared by the Irish Guards on the social media platform X (formerly Twitter), Princess Kate wrote, "I wanted to write and let you know how proud I am of the entire Regiment ahead of the Colonel's review and Trooping of the [Color.] I appreciate everyone trooping this year has been practicing for months and dedicating many hours to ensuring their uniforms and drill are immaculate."

The Princess of Wales, who was appointed as the honorary Colonel of the Irish Guards by King Charles III last year, acknowledged the honor of her role and expressed her deep regret for being unable to attend the rehearsal. "Being your colonel remains a great honor, and I am very sorry that I'm unable to take the salute at this year's Colonel's Review," she wrote. "Please pass my apologies to the whole Regiment, however I do hope that I am able to represent you all once again very soon."

Princess Kate's absence from the public eye has been noticeable since she revealed her cancer diagnosis in March, following major abdominal surgery in January. The 42-year-old princess has undergone chemotherapy treatment for an unspecified type of cancer, and some reports suggest that she may not be seen in public for the remainder of the year.

Despite her ongoing health concerns, Princess Kate took the time to send her best wishes to the Irish Guards, writing, "Please send my very best wishes and good luck to all involved." In her absence, Lieutenant General James Bucknall will replace the princess at the Colonel's Review, according to a Kensington Palace spokesperson.

It remains unclear whether Princess Kate will attend the Trooping the Colour ceremony on June 15, although The Mirror reported that she is "considering" appearing on the balcony of Buckingham Palace with the rest of the royal family. The event, which is a 260-year-old tradition, involves troops in full dress uniform parading past the king with their ceremonial flag, known as their "color."

The Irish Guards responded to Princess Kate's letter on X, expressing their gratitude and well-wishes for her recovery. "We continue to wish Her Royal Highness well in her recovery and send Her our very best wishes," they wrote.

The past year has been challenging for the British Royal Family, with both Princess Kate and King Charles III undergoing cancer treatment. Despite these difficulties, the monarch has eased back into public duties, attending commemorations this week for the 80th anniversary of D-Day.