Kate Middleton attends church in Scotland despite cancer battle.

Kate Middleton made a public appearance despite her ongoing battle with an undisclosed form of cancer.

On Sunday, the Princess of Wales was observed entering Crathie Church on the Balmoral Estate with her husband, Prince William, and their eldest child, Prince George.

The DailyMail in the U.K. reports that the trio later joined King Charles, Queen Camilla, Prince Edward, Sophie, Duchess of Edinburgh, and their son James Wessex.

Middleton made her first public appearance in over a month, looking happy and adding a touch of flair with a feathered hat.

Balmoral Castle, a sprawling, 50,000-acre estate, is where the royal family traditionally spends the rest of the summer months in private. Queen Elizabeth II referred to it as her "paradise in the highlands," according to Perthnow, an Australian website.

In 2022, at the age of 96, England's longest-reigning monarch passed away at Balmoral Castle.

It has been reported that Kate, William, and their three children will spend time together at Anmer Hall, their country home in Norfolk before school begins.

The 42-year-old will return to public duties on Sept. 5 in London by attending the "Homelessness: Reframed" exhibit at the Saatchi Gallery.

In January, Middleton was hospitalized for unspecified abdominal surgery, which led to relentless speculation on social media about her health. In March, she announced that she had been diagnosed with cancer and was undergoing chemotherapy.

The British royal requested "privacy while I complete my treatment."

The princess later confessed in a private letter that "there are good days and bad days." She also stated her intention to participate in "a few public engagements during the summer, but equally aware that I am not yet out of the woods."

Kate attended Trooping the Colour in June and Wimbledon a month later, but skipped Garter Day, Royal Ascot, and a Japan state visit to the U.K.

Kate is currently engaged in a waiting game, adhering strictly to her doctor's orders and hoping that upcoming tests will indicate that the chemo has been successful, as stated by Christopher Andersen, author of "The King," in a conversation with Planet Chronicle Digital.

Andersen stated that it is a stressful and debilitating time for Kate, which is intensified by the fact that the world is also holding its breath along with her.

Middleton has been quietly busy behind palace doors while relying on her family for support during tough days, as Andersen told Planet Chronicle Digital.

"Kate occasionally concentrates on causes she has long supported, such as mental health awareness. She is also seen running errands with her mother. However, Kate's primary responsibility at present is ensuring that her three children enjoy their summer holiday as they always do, which includes swimming, horseback riding, and spending time with their cousins at Anmer Hall, their countryside home on the Sandringham estate."

"Kate cooks and bakes for the family when she feels up to it, plays cards and board games with William and the children, especially Scrabble, which is their favorite. Since she is now forced to stay at home due to circumstances, Kate has been reflecting on her work as a photographer and sending out a message of hope and optimism to the world."

Andersen pointed out that the family would make their annual pilgrimage to Balmoral.

"Andersen stated that Kate is resolute in ensuring that Prince George, Princess Charlotte, and Prince Louis do not miss out on summer activities due to their mother's health problems, as that is the kind of person she is."

The Associated Press contributed to this report.