Kate Middleton celebrates her 43rd birthday after being diagnosed with cancer

Kate, Princess of Wales, turns 43 on Thursday, capping a tumultuous year for the mother-of-three and wife of Prince William.

Kate, who was born on January 9, 1982, is expected to spend her birthday alone with William and their children – Princes George and Louis and Princess Charlotte – at home in Windsor, England.

William shared a tribute to Kate on social media on Thursday, writing: “To the most amazing wife and mother. The strength he has shown over the past year has been remarkable. George, Charlotte, Louis and I are so proud of you. Happy Birthday Catherine, we love you.”

William signed the post with his initials “W”, indicating that he wrote the message himself. The post also included a photo of Kate taken by photographer Matt Porteous during the summer in Windsor, according to Kensington Palace.

On her birthday last year, Kate was a week away from being admitted to a London hospital where she would undergo what Kensington Palace described at the time as “planned abdominal surgery”.

Kate spent almost two weeks in hospital before being discharged at the end of January.

Since her hospitalization, Kate has taken an extended time off from her public royal duties, leading to a frenzy of speculation online about her well-being and whereabouts.

Amid speculation about her health, Kate publicly apologized for a photo of herself with her children that was shared on social media for Mother’s Day and later revealed to have been edited. In her apology, Kate apologized for any “confusion” these changes caused.

Less than two weeks later, on March 22, Kate revealed in a video message that she had been diagnosed with cancer.

“I had major abdominal surgery in London in January and at the time it was thought to be non-cancerous. The operation was a success,” Kate said in the video message. “However, tests after the operation revealed the presence of cancer. So my medical team advised me to undergo a course of preventive chemotherapy and I am now in the early stages of this treatment.’

Kate did not share the type of cancer she was diagnosed with or details about her treatment.

She remained out of the public eye for several weeks after her announcement before joining the royal family in Trooping the Color in May.

In September, Kate announced that she had finished chemotherapy and was focusing on staying “cancer free” and gradually returning to work.

In the following months, Kate made several public appearances, including traveling to Southport, England, with William and hosting her annual carol service at Westminster Abbey.

Kate’s last public appearance before her birthday was on Christmas morning.

She joined William as well as Charlotte, George, Louis and other members of the royal family as they walked to church in Sandringham on Christmas morning, following royal tradition.