The video in the player above is from a previous report.
While meeting with World War II veterans in Portsmouth, England, on Wednesday to mark the 80th anniversary of D-Day, William was asked by one veteran whether Kate was "getting any better."
In response, William said, "Yes," adding, "She would've loved to be here today."
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Kate, who shares three children with William, announced in a video message in March that she had been diagnosed with cancer after undergoing abdominal surgery in January.
The type of cancer has not been disclosed. According to Kensington Palace, Kate started a course of preventative chemotherapy in late February.
Kate has remained out of the public eye since announcing her diagnosis. The palace has said of her return to official duties that she will only do so when she is cleared by her medical team.
William also took a short time off from public duties after Kate's diagnosis was announced. He returned to work in mid-April, visiting a nonprofit organization in Surrey, where volunteers gave him cards of well-wishes for Kate.
While marking the 80th anniversary of D-Day, William stepped in for his father, King Charles III, who was also diagnosed with cancer this year.
On Thursday, in Charles' absence, William joined heads of state at the international commemorative ceremony at Omaha Beach.
A royal source told ABC News that Charles did not attend the ceremony due to health reasons.
RELATED: King Charles III has cancer, receiving treatment, Buckingham Palace says
"We have to prioritize and protect his continued recovery," the source said. "On that basis, each event, day has to be carefully calibrated, and given His Majesty's other commitments on the day, it was advised that the international event later in the afternoon may be a step too far at this stage."
When the king returned to public duties in late April, the palace noted that Charles was still undergoing treatment but had been approved to remove some public-facing duties.
The palace has not disclosed publicly what type of cancer Charles was diagnosed with or what type of treatment he is undergoing.
Charles joined his wife Queen Camilla, as well as William, in meeting with veterans on Wednesday in Portsmouth.