The Princess Of Wales has cancer, and is undergoing preventative chemotherapy.
In a personal video message tonight (Friday) she said that following abdominal surgery in January she has since been diagnosed.
Catherine said it was a "huge shock" after an "incredibly tough couple of months". But she sent a positive message, saying: "I am well and getting stronger every day."
Born Catherine Elizabeth Middleton, she married Prince William, The Prince of Wales, at Westminster Abbey on 29 April 2011.
The couple have have three children, Prince George, Princess Charlotte and Prince Louis.
Catherine, who is also the Duchess of Cornwall, is 42 and holds patronage with over 20 charitable and military organisations including the Anna Freud Centre, Action for Children, SportsAid, and the National Portrait Gallery.
In January Buckingham Palace announced that the Princess had been admitted to hospital for planned abdominal surgery. They said it was successful and it was expected she would remain in hospital for ten to fourteen days, before returning home to continue her recovery.
They said that based on medical advice, she was unlikely to return to public duties until after Easter.
On Mothers Day the Prince and Princess of Wales issued a public photo of Catherine posing with their children.
But later news agencies "killed" the photo after revealing it had been digitally altered.
The Palace announced in February that King Charles, who is 75, has cancer and was undergoing treatment. He cancelled his engagements. What type of cancer he was diagosed with was not revealed.
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