Kate Middleton and Prince Harry's communication lines are still open for each other, according to a source.

The Princess of Wales announced her cancer diagnosis in March. Following her health update, many hoped it would pave the way for a reconciliation between the Sussexes and the royal family. According to an unnamed tipster, Prince William's wife confided in his brother about her health battle for support, but Markle was initially left in the dark.

"Everyone assumes Kate doesn't like Harry, but they have a special bond that not many people really understand," the source told Life & Style. "She and Harry were extremely close at one time. She's confided in him during some of her darkest moments, and now that includes her cancer battle. Kate's leaned on Harry for support."

Prince Harry and Kate Middleton
Kate Middleton and Prince Harry speak as they host a tea party in the grounds of Buckingham Palace to honour the children of those who have died serving in the armed forces on May 13, 2017 in London, England.
(Photo : Andrew Parsons - WPA Pool/Getty Images)

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The source claimed that Prince Harry and Middleton's communication just sort of happened, and it left Markle "blindsided." However, the gravity of Middleton's illness reportedly convinced the Duchess of Sussex to set aside their beef.

"Meghan was blindsided and felt, maybe, a bit betrayed at first," the source continued. "She accepts that she wasn't around when Kate and Harry first became friends."

Markle also reportedly "really respected and admired" her sister-in-law "before things got bad between all of them." Just like Markle, the Prince of Wales was also allegedly caught off guard that Middleton and Prince Harry were already on speaking terms.

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Prince William, Kate Middleton, Meghan Markle and Prince Harry
Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge, Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex attend a service marking the centenary of WW1 armistice at Westminster Abbey on November 11, 2018 in London, England.
(Photo : Paul Grover- WPA Pool/Getty Images)

"He was surprised and concerned," the source said, noting that the heir apparent "continues to have trust issues with Harry."

However, the insider noted that Prince Harry and Prince William are very different, so there are things much easier for Middleton to discuss with the former than with the latter.

"While Kate loves William and she does confide in her husband, it's easier to talk about certain things with Harry," the tipster added. "He's always been a good listener."

Enstarz could not independently verify the claims.

Prince William, Kate Middleton and Prince Harry
Prince Harry, Kate Middleton and Prince William laugh as they host a tea party on the grounds of Buckingham Palace to honour the children of those who have died serving in the armed forces on May 13, 2017 in London, England.
(Photo : Andrew Parsons - WPA Pool/Getty Images)

Prince Harry was very close to the Duke and Duchess of Cambridge. He used to be Prince William and Middleton's wingman, and he previously said that Middleton was the sister he never had.

However, there was an apparent tension after Prince Harry and Markle stepped back from their royal duties and moved to the United States. According to Ingrid Seward, a royal biographer and editor of Majesty magazine, Prince Harry's relationship with his brother and sister-in-law became "disruptive" when Markle joined the picture.

"Every time he had a new girlfriend, the first person that would meet her would be Kate," the "My Mother and I" author said, highlighting Prince Harry and Middleton's close bond. "And then Meghan came into the mix, and it was disruptive. It wasn't like the other girlfriends. There [wasn't] that warm feeling. I think it started on the wrong foot."

Prince William, Kate Middleton, Meghan Markle and Prince Harry
Catherine, Princess of Wales, Prince William, Prince of Wales, Prince Harry, Duke of Sussex, and Meghan, Duchess of Sussex meet members of the public on the long Walk at Windsor Castle on September 10, 2022 in Windsor, England.
(Photo : Kirsty O'Connor - WPA Pool/Getty Images)