Always wary of leaks to the press,Kate Middletonhad been open about hercancer diagnosisto some, but other close friends and confidants were unaware.

“It was a heck of a shock,” one tells PEOPLE exclusively in this week’scover story

Adds a former palace aide: “The circle of knowledge was very tight. "

In a video that sent shockwaves around the globe on March 22, Princess Kate, 42, revealed that she had been diagnosed with cancer and was undergoing chemotherapy. The royal mom, so famous for her unerring poise, spoke about initially keeping the diagnosis private for “the sake of our young family,” her voice cracking at the reference toPrince George, 10,Princess Charlotte, 8, andPrince Louis, 5, whom she shares withPrince William.

Kate Middleton visits the Army Training Centre Pirbright on September 16, 2022.Samir Hussein/WireImage

Catherine, Princess of Wales meets with military personnel during a visit to Army Training Centre Pirbright on September 16, 2022 in Guildford, England. The Prince and Princess of Wales are visiting the training centre to meet troops from the Commonwealth who have been deployed to the UK in order to take part in the funeral of Queen Elizabeth II, which will take place on September 19.

Samir Hussein/WireImage

Says a source close to the royal household, “She held it together.”

Behind the scenes, the Princess of Wales has been taking steps to prioritize her health and well-being, but she hasn’t been in complete seclusion. Both she and Prince William, 41, have been spotted at their children’s sports events and lessons in recent weeks. On March 16, the couple were photographedrunning errandstogether at Windsor’s Farm Shop.

“Having fun together when they can is very important,” says a family friend. “This is about her feeling supported. She doesn’t feel isolated at all.”

PEOPLE Magazine, April 8, 2024.

Kate Middleton People cover 040824

While Kate’s health crisis has strengthened the safety net around her, it has also highlighted the royal family’s ongoing estrangement fromPrince HarryandMeghan Markle, who learned the news at the same time as the rest of the world. However, they privately reached out to William and Kate following the announcement and publicly released a statement: “We wish health and healingfor Kate and the family, and hope they are able to do so privately and in peace.”

Princess Charlotte, Prince William, Prince George, Mia Tindall, Prince Louis and Kate Middleton attend church on Christmas at Sandringham on December 25, 2023.Stephen Pond/Getty

Princess Charlotte, Prince William, Prince of Wales, Prince George, Prince Louis, Mia Tindall and Catherine, Princess of Wales attend the Christmas Morning Service at Sandringham Church

Stephen Pond/Getty

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The Prince of Wales will resume public duties after George, Charlotte and Louis return to Lambrook School on April 17, and Kate, who will remain out of the public eye during her treatment, may join in events when she feels able. But palace sources say that would not necessarily signal areturn to royal duties— that decision will rest on doctors’ advice. For now, her focus is on her full recovery, with her family there to support her.

“She has the inner strength, the support of her husband and her extraordinary family, so she can focus on what’s important,” says Ailsa Anderson, a former spokeswoman forQueen Elizabeth, “which is her getting back to strength.”

source: people.com