Kate Middleton being comforted by 'extraordinary resilience' of her three children amid cancer treatment

LONDON, UK: Amid Kate Middleton's cancer treatment, her children - Prince George, Princess Charlotte, and Prince Louis - are providing a special source of support for the Duchess of Cambridge.

A longtime family friend shared exclusively with PEOPLE in this week's cover story, "You take heart from the extraordinary resilience of children."

Kate Middleton's kids bring comfort amid cancer battle

Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5, are reportedly helping the Prince and Princess of Wales navigate through this health crisis by uplifting them with their smiles and positivity. The family friend remarked, "Having fun together when they can is very important."

"The children are at the center of their world," the friend added.

The insider added that Prince William, 41, and Princess Kate, 42, prioritize spending time with their kids.

This emphasis on family was also evident in the timing of Princess Kate's cancer announcement. She waited until after her children were on Easter holiday break from school to make the public disclosure.

With George, Charlotte, and Louis not scheduled to return to school until later in April, the family found an opportunity for private time together.

"We now understand the logic of the timing — waiting for the children to break up from school. And she struck a pitch-perfect note," royal biographer Sally Bedell Smith told PEOPLE about Princess Kate’s video message on March 22 that sent shockwaves around the world.

In the self-written address, Kate revealed that she was undergoing "preventative chemotherapy" after tests following her abdominal surgery in January detected the presence of cancer. She emphasized her focus on healing and reassured her children that she would be okay.

Describing her approach to discussing her cancer treatment with her kids, Princess Kate said, "I am well and getting stronger every day by focusing on the things that will help me heal; in my mind, body, and spirits."

Prince William and Princess Kate attempt to heal rift with Prince Harry and Meghan Markle

Rumors of ongoing tensions within the British royal family have sparked intrigue, with reports suggesting that Prince William and Kate Middleton are taking proactive steps to mend their relationship with Prince Harry and Meghan Markle.

According to insights shared by a royal expert, the Duke and Duchess of Cambridge have reached out to the Sussexes in an attempt to reconcile their differences.

In an exclusive interview with The Mirror, royal author Tom Quinn unveiled that William and Kate have extended an invitation to Harry and Meghan, urging them to bring their children for a visit to the United Kingdom.

Quinn disclosed, "There is no way Meghan would bring the children to the UK. William and Kate have suggested that Meghan and Harry bring the children and that the two couples and their families try to make up, but the suggestion is not leading anywhere so far."

Meghan and Harry have been vocal about their grievances, airing criticisms and making damning allegations against certain family members during various media appearances.