Kate Middleton Helped Prince William 'Warm Up' to Queen Camilla

Prince William and Queen Camilla's once fractured relationship relationship has evolved over the years, and Kate Middleton might be the person to thank for the Prince of Wales' change of heart.

According to an insider, Camilla and William have "come a long way."

The source credited the Prince of Wales' "change of heart" to the Princess of Wales being "accepting of Camilla" years before the other royals embraced the queen consort.

Before Princess Diana passed, she branded Camilla as the third person in her marriage to King Charles — so due to Camilla and Diana's history, William and Prince Harry had reservations about their stepmother.

When Charles and Camilla were blending their families, the former Duchess of Cornwall was nervous about her first interaction with William and Harry.

"Camilla was so terrified at the prospect of meeting William that when she finally met him at Clarence House, she was trembling like a leaf and needed a vodka and tonic afterward," royal biographer Christopher Andersen claimed. "That seems perfectly understandable since Camilla — and the world — knew she had destroyed the marriage of William’s parents, Charles and Diana."

However, nowadays, "they both like the fact that Camilla’s normal and makes Charles less stuffy," a family friend said. "Kate likes her because she brings a real-life relatability into the family. She’s not all about the courtiers waiting on hand and foot. Camilla’s real like Kate is."

As OK! previously reported, experts believe Kate and Charles' cancer diagnoses helped William and Camilla grow closer.

"Prince William initially couldn’t stand Camilla," expert Hilary Fordwich told an outlet. "[But] he has come to appreciate her steadfast dedication to duty. They have become closer and have bonded over their spouses coping with cancer treatment."

"Camilla has a calming influence on King Charles. Prince William appreciates that she also makes his father happy," Fordwich added.

Camilla and Charles tied the knot in 2005, but the royal didn't try to take Diana's place in William and Harry's lives.

"William was very cordial to Camilla, and their relationship has always been civil," Andersen said. "That is in part because Camilla has been shrewd enough not to ever try to instruct William in any way."

"The fact is, despite her earthly reputation, Camilla is not a mom type. She was never a hands-on mother with her own children and certainly would not have interfered in Charles’ relationship with his children," he added.

Camilla and William aren't the only royals whose connection grew amid health crises, as Charles and Kate's strong bond was on display during Trooping the Colour.

“The protocol is that traditionally Kate and William would be standing next to each other and the King and Camilla standing next to each other," former royal butler Grant Harrold said on behalf of Slingo. "It is planned but it is also changing the protocol to show the King and Kate united with each other and going through similar battles, so I would say this is down to the King’s preference. The balcony is all orchestrated, but I have a feeling the King said to Kate, ‘You stand next to me.'"

Us Weekly spoke to sources about Kate and William's relationship with Camilla.