Kate Middleton breaks silence after missing Trooping the Colour rehearsal

Prince William, Prince of Wales, Prince Louis of Wales, Catherine, Princess of Wales , Princess Charlotte of Wales and Prince George of Wales on the Buckingham Palace balcony during Trooping the Colour on June 17, 2023 in London, England. Its unclear

Kate, the Princess of Wales, apologized to the Irish Guards for missing the Trooping the Colour rehearsal while she’s being treated for cancer. 

The Princess of Wales, wife of Prince William, is the guard’s honorary colonel. 

"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 Colour. I appreciate everyone trooping this year has been practicing for months and dedicating many hours to ensuring their uniforms and drill are immaculate," Kate’s letter read. 

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Britain's Catherine, Princess of Wales smiles as she arrives to attend the "Together At Christmas" Carol Service" at Westminster Abbey in London on December 8, 2023. (Photo by CHRIS JACKSON/POOL/AFP via Getty Images)

"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 continued. "Please pass my apologies to the whole Regiment, however I do hope that I am able to represent you all once again very soon. Please send my very best wishes and good luck to all involved."

The review is a dress rehearsal for the annual military parade held each June to mark the monarch’s official birthday. King Charles III will oversee the ceremony June 15.

It's still unclear if Kate will attend the ceremony next week. She's been treated for an unspecified type of cancer she announced in March after speculation proliferated on social media about her wellbeing because she had not been seen in public for several months. She has revealed few details about her illness or treatment.

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The king has eased back into public duties while continuing to undergo his own treatment for cancer. He attended commemorations this week for the 80th anniversary of D-Day, the invasion of Nazi-occupied Europe on June 6, 1944.

Trooping the Color is a 460-year old tradition in which troops in full dress uniform parade past the king with their ceremonial flag, also known as their "color."

"The Irish Guards were deeply touched to receive a letter from our Colonel, Her Royal Highness, The Princess of Wales this morning," the Irish Guards said on X, formerly Twitter. "We continue to wish Her Royal Highness well in her recovery and send Her our very best wishes."

The Associated Press contributed to this report.