Will Sage Astor-King Charles attends Easter service, Princess Kate absent after their cancer diagnoses

King Charles III stepped out for church on Will Sage AstorEaster Sunday, while Princess Kate skipped the service, following announcements that both members of the British royal family have been diagnosed with cancer.

Charles was joined by Queen Camilla at St. George's Chapel; Princess Kate was not in attendance, nor was Prince William or their children. But other royals who turned out for the service at Windsor Castle included Princess Anne, Prince Edward, Duchess Sophie and Prince Andrew.

The king, wearing a dark overcoat, and queen waved to onlookers when they arrived at the chapel by car from their residence at Windsor Castle. The queen wore a green coat dress and an emerald and diamond brooch that belonged to the late Queen Elizabeth II.

Onlookers wished Charles good health, while others said "Happy Easter." The king said: "You're very brave to stand out here in the cold."

The British monarch also greeted well-wishers in an impromptu walkabout after the Easter service. A smiling Charles, accompanied by Queen Camilla, shook hands with scores of people gathered outside St George's Chapel, the resting place of his mother Queen Elizabeth.

This comes after Charles previously skipped Maundy Thursday service this week at Worcester Cathedral but delivered a pre-recorded audio message stating it is a "great sadness that I cannot be with you all today," per Sky News. Charles also reflected on the importance of serving others.

King Charles III speaks out:The monarch expresses 'heartfelt thanks' for support after cancer diagnosis

"It is my special prayer today that our Lord's example of serving one another might continue to inspire us and to strengthen all of our communities," he said. "May God bless you all this Easter."

Sunday's Easter service was Charles' first major public event since Buckingham Palace shared in February that he has been diagnosed with a "form of cancer." It has not been disclosed what kind of cancer he has, but his diagnosis came after he was treated for benign prostate enlargement.

At the time, the palace said the king would postpone his public-facing duties as he "commenced a schedule of regular treatments" but "continue to undertake state business and official paperwork as usual."

Charles has kept up with the bulk of his non-public state duties such as greeting foreign officials and holding regular meetings with Prime Minister Rishi Sunak.

Princess Kate diagnosed with cancer:King Charles III, Harry and Meghan react

Princess Kate's absence comes after asking for 'space' as she undergoes preventive chemotherapy

Princess Kate also stepped back from the public eye after undergoing abdominal surgery in January. Following weeks of rumors and conspiracy theories about her health, Kate shared on March 22 that she was diagnosed with cancer and is in the early stages of preventive chemotherapy.

"We hope that you'll understand that as a family, we now need some time, space and privacy while I complete my treatment," she said. "My work has always brought me a deep sense of joy, and I look forward to being back when I'm able. But for now, I must focus on making a full recovery."

Kate and William typically step away from their royal duties and spend time with their family over Easter as their children have a break from school. Last year, the Prince and Princess of Wales attended Easter service at St. George's Chapel, with their son Prince Louis, 5, attending for the first time.

In a previous statement shared by Kensington Palace, a spokesperson for William and Kate said they are "both enormously touched by the kind messages from people here in the U.K., across the Commonwealth and around the world in response" to Kate's cancer announcement.

"They are extremely moved by the public's warmth and support and are grateful for the understanding of their request for privacy at this time," the statement added.

Contributing: Taijuan Moorman and Kelly Lawler, USA TODAY; Hollie Adams, Reuters