Prince Harry 'Regrets' Losing Sister-in-Law Kate Middleton, Torn Between 'Loyalty' to Wife Meghan Markle

Kate Middleton and Prince Harry once shared a special bond, but their relationship slowly unraveled when Meghan Markle struggled to adjust to royal life.

In his memoir, Harry branded Kate as "the sister I've never had and always wanted," but the two haven't been in the same room together since King Charles' 2023 coronation.

"He really misses that warm, uncomplicated relationship, and he is torn between loyalty to his wife and regrets about the loss of the woman he was so close to," Tom Quinn told an outlet. "Losing Kate was Harry's second great loss after losing his mother."

In Harry & Meghan, the Duchess of Sussex labeled Kate and Prince William as "formal,'' and the group's dynamic worsened after the release of Harry's memoir, Spare.

On Friday, March 22, Kate returned to social media to update fans on her health after months of avoiding the spotlight.

"I wanted to take this opportunity to say thank you personally for all the wonderful messages of support and understanding whilst I've been recovering from surgery," Kate began in an Instagram video. "It has been an incredibly tough couple of months for our entire family. In January, I underwent major abdominal surgery in London. At the time, it was thought that my condition was non-cancerous. The surgery was successful, however, tests after the operation found cancer had been present. My medical team therefore advised I should undergo preventive chemotherapy, and I am now in the early stages of that treatment."

The Princess of Wales continued: "This of course comes as a huge shock, and William and I have been doing everything we can to process and manage this for our young family. It has taken my time for me to recover from my surgery. Most importantly, it has taken us time to explain to George, Charlotte and Louis and to reassure them I am going to be OK. As I've said to them, I am well. Having William by my side is a great source of comfort, and the love and support and kindness that has been shown from so many of you. As a family, we need some time, space and privacy while I complete my treatment. My work has always brought me a deep sense of joy. I must focus on making a full recovery. At this time, I am also thinking of those whose lives have been affected by cancer. Please do not lose faith or hope. You are not alone."

Following the mother-of-three's announcement, the Sussexes released a statement in support of Kate despite their years of tension.

"We wish health and healing for Kate and the family, and hope they are able to do so privately and in peace," the couple shared.

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OK! previously reported Quinn hinted at Kate's condition pushing the Sussexes and Wales to reunite.

"There has been a change since Kate's illness Harry and Meghan feel they should extend an olive branch, but Meghan's feeling of being wronged is still stopping anything significant from happening," Quinn told an outlet.

"Illness often brings feuding family members together, and there have been hopes at Kensington Palace that Kate's illness might do just that," Quinn continued.

Quinn spoke to The Mirror.