Kate Middleton makes public return at King Charles' birthday parade ...

LONDON — It’s King Charles III’s official birthday, but all eyes will be on Kate, the Princess of Wales.

Kate, 42, is making her return to the public eye Saturday after sharing an update on her cancer treatment. She announced Friday that she would attend the Trooping the Colour ceremony in London for her first official public appearance since she revealed the diagnosis earlier this year.

The annual military ceremony celebrates the British monarch’s official birthday, and Charles will also attend after his cancer diagnosis.

In her personal statement, Kate wrote she was “not out of the woods yet” and that she had “good days and bad days.” She said she was “making good progress,” but that her treatment would continue for a few more months.

Her attendance at Saturday’s parade will be seen as a significant positive step after a monthslong absence that fueled widespread speculation.

Kate and Prince William’s children, George, 10, Charlotte, 8, and Louis, 5, have also largely been out of the public eye in recent months. They will join her at Saturday’s event, arriving with her in a carriage down the Mall before watching alongside her on the Horse Guards Parade grounds and then making a royal balcony appearance.

The family traditionally gathers on the balcony at the end of each year’s event to watch a flyover by the Royal Air Force.

The event in central London will see Charles carry out the review of the guardsmen and officers from a carriage alongside Queen Camilla, rather than on horseback as he did last year.

By inspecting the troops on horseback at his first official birthday parade, Charles revived a tradition that his mother, Queen Elizabeth II, gave up in 1986 when she was 60.

William will be on horseback this year.

Also known as the King’s Birthday Parade, the ceremony has been an annual event since 1760. It is the British military’s annual tribute to the monarch and marks their official birthday.

Charles’ actual birthday is Nov. 14.

The traditional show of military pomp and pageantry will feature soldiers marching in scarlet coats and bearskin fur hats accompanied by music played by military bands.

Among the 242 horses due to take part in this year’s event will be three members of the Household Cavalry that were injured after being spooked by noise in London earlier this year.

Charles, who himself was diagnosed with cancer in February, has also been undergoing treatment. Doctors discovered the disease after he was hospitalized with an enlarged prostate, although the palace has said that he does not have prostate cancer.

Both Charles and Kate have declined to specify what type of cancer they have or details about their prognoses.

The 75-year-old monarch has attended several engagements since he resumed public duties last month, including D-Day memorial services in France.