Kate Middleton has completed cancer treatment, will return to light public duties

Britain's Kate Middleton

Catherine, Princess of Wales, says she is relieved to have "finally completed" chemotherapy treatment and plans to undertake light engagements through the end of the year.

The 42-year-old British royal, who revealed in March that she had an undisclosed form of cancer, shared the update in a personal video on Monday that featured several candid moments with her husband, Prince William, and their three children, Princes George and Louis and Princess Charlotte. Catherine, formerly Kate Middleton, said that the last nine months have been "scary" and "incredibly tough for us as a family."

"Doing what I can to stay cancer-free is now my focus. 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," she said. "I am, however, looking forward to being back at work and undertaking a few more public engagements in the coming months when I can."

The video, which played as a cinematic reel featuring the royal family, was filmed last month by Will Warr while the royals were in Norfolk, Kensington Palace said.

Catherine began treatment in late February; however, the palace would not say when she received her last treatment. The palace also declined to state what type of cancer she has and what stage she was diagnosed in, citing the princess' "right to medical privacy." The princess and palace only disclosed that her cancer was discovered after she had “major abdominal surgery” in January and that she was being treated with preventive chemotherapy, a secondary treatment that in the U.S. is known as adjuvant chemotherapy.

Read more: Catherine making 'good progress' in cancer treatment as she announces partial public return

While she will undertake a handful of public engagements in the coming months, Catherine is not taking them immediately due to a period of period of recovery from treatment, The Times has confirmed.

"The last nine months have been incredibly tough for us as a family. 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," Catherine said in the video, which features the family hiking and spending time in nature. "The cancer journey is complex, scary and unpredictable for everyone, especially those closest to you.

"With humility, it also brings you face to face with your own vulnerabilities in a way you have never considered before, and with that, a new perspective on everything," she continued. "This time has above all reminded William and me to reflect and be grateful for the simple yet important things in life, which so many of us often take for granted. Of simply loving and being loved."

Catherine said that she enters "this new phase of recovery with a renewed sense of hope and appreciation of life," and that she and William, who is the first in line to the British throne, are grateful for the support they have received during the past year.

"Everyone’s kindness, empathy and compassion has been truly humbling," she said, adding, "To all those who are continuing their own cancer journey — I remain with you, side by side, hand in hand. Out of darkness can come light, so let that light shine bright."

Read more: Prince William says that Kate Middleton is getting better amid cancer treatment

Catherine is set to return to "a light program of external engagements for the remainder of the year, reflecting the need to focus on making a full recovery," said a person close to the royal family who was not authorized to speak publicly on the matter. Decisions about 2025 will be made according to medical advice, but she has started to work from home and will continue to do so over the coming months, the person said.

The former upper-middle-class commoner, who married into the British royal family in 2011, has made sparing public appearances and provided a few progress reports since revealing her diagnosis. She last appeared at a public engagement on Aug. 25 when she attended church services near Balmoral Castle in Scotland with William, King Charles III and Queen Camilla. In June, she attended the festive Trooping the Color, which marked her first public engagement since last December.

In the months in between, speculation ran amok about the princess' retreat from the public eye and her royal duties, fueling broad concern about her whereabouts and well-being. Her poignant cancer announcement in March came on the heels of reports that her medical records at the London Clinic were allegedly breached by hospital staffers and months after Buckingham Palace announced that the king had been diagnosed with cancer.

Read more: Don't blame the public for failing Kate Middleton. Blame the palace

William resumed public duties last week after taking the summer off and backing out of a few high-profile events earlier this year due to his family members' illnesses. He, Catherine and their daughter Charlotte notably made a rare public appearance at the Wimbledon final in July, and he and Catherine took part in a video for social media congratulating British Olympians after the Paris Games.

Catherine will not be joining him Tuesday during a trio of engagements he has in Wales, The Times has confirmed. But she is likely to appear at the Cenotaph on Whitehall in London on Remembrance Sunday in November and will likely host the Carol Service in December.

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This story originally appeared in Los Angeles Times.