Catherine, the Princess of Wales, announced on Monday that she had completed chemotherapy for her cancer, lifting a dark cloud from the British royal family after an anxious period in which she and her father-in-law, King Charles III, had both been stricken with serious illness.

Speaking in a video, Catherine said, “As the summer comes to an end, I can’t tell you what a relief it is to have finally completed my chemotherapy treatment.”

“Doing what I can to stay cancer free is now my focus,” she continued. “Although I have finished chemotherapy, my path to healing and full recovery is long and I must continue to take each day as it comes.”

Catherine said she looked forward to returning to work, and will undertake a light schedule of public events for the rest of the year. She is expected to attend a ceremony honoring those killed in war at the Cenotaph monument in November, one of the most somber dates on the royal calendar.

Kensington Palace, where Catherine and her husband, Prince William, have their offices, has not confirmed the nature of Catherine’s cancer.

Speaking in a video taped last month in Norfolk, she described her ordeal since being hospitalized in January.

“The last nine months have been incredibly tough for us as a family,” Catherine said. “Life as you know it can change in an instant, and we have had to find a way to navigate the stormy waters and road unknown.”

This is a developing story.