Kate, Britain's Princess of Wales, will attend the men's singles final at Wimbledon on Sunday, set to mark her second public appearance since surgery six months ago revealed the presence of cancer.
The Kensington Palace said on Saturday,
Kate, 42, who is undergoing preventative chemotherapy, is an avid tennis fan and is patron of the All England Lawn Tennis and Croquet Club Wimbledon, which hosts the annual tennis championships.
The princess, the wife of heir-to-the-throne Prince William, returned to public duties in June at "Trooping the Colour," the annual military parade marking King Charles's official birthday. She said she hoped to attend other events over the summer.
"I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days," she said in a personal written message ahead of that appearance.
"My treatment is ongoing and will be for a few more months," said the princess, who is often known by her maiden name, Kate Middleton.
Her office, Kensington Palace, has declined to give specific details about the type of cancer or her medical condition other than to say the treatment started in February.
Charles, 75, has also been undergoing cancer treatment. He returned to public duties in April and has remained busy, although his agenda commitments are limited to minimise risks to his recovery.
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