Prince William, Kate Middleton's Marriage Is 'Very Much A Partnership': Royal Expert

Prince William and Kate Middleton are the faces of the monarchy's future, according to a royal expert.

The Prince and Princess of Wales celebrated their 12th wedding anniversary last month. They also played key roles in King Charles' coronation at Westminster Abbey Saturday.

Nick Bullen, the co-founder of True Royalty TV, spoke about their marriage and their role as the youthful face of the future of the monarchy following the coronation. Bullen credited their partnership in their marriage and royal duties as senior members of the royal family.

"I think the secret of the Wales' marriage is that it is very much a partnership," he told Fox News Digital. "If you look at other royal relationships that have worked, they've been partnerships."

He added that Middleton is very much part of the decision-making. The Princess of Wales is also someone who reportedly knows how to work with her temperamental husband.

"I'm told very clearly that the Princess of Wales is very much part of the decision-making process in Kensington Palace," said Bullen. "She knows how best to work with William. And William, as we know from the stories of his explosions with Prince Harry, can have a temper. And I think the Princess of Wales is very good at managing the Prince of Wales. It's a partnership, and he knows how good she is and what a useful tool she is for the royal family."

He recounted the marriage between the late monarch Queen Elizabeth and Prince Philip and how the latter supported the former.

"Prince Philip and the queen were a partnership," he shared. "She might have been the woman on the stamps and the coins and the head of state, but they worked together. I knew Philip... I have been in the room [when] he said he knew his job was to work with her and support her, and that his service was to his monarch."

He noted how Prince William and Middleton's lives changed after the Queen's passing. From being second in line to the throne, the Prince of Wales became the heir, which changed everything for the couple.

"He was always serious about his duty, and he always knew what his destiny was, but now it's there... I think you can see the seriousness in the Wales' in a way that wasn't there even a year ago," Bullen said of Prince William and his family.

"We've recently been working with him in his role as president of the BAFTAs," Bullen continued. "And it was very interesting – his whole demeanor was, in some ways, more serious than I'd seen it before. The things that he wanted to be involved in were very serious causes that had a real purpose. He doesn't really want to talk about himself. The Princess of Wales doesn't want to talk about herself. They want to really focus on the causes and the things that are important to them, as opposed to about them."

The Duke of Cambridge played several roles during the coronation. He delivered his pledge of loyalty and allegiance to the King. He also served as the Stole Royal and Robe Royal, who assisted in putting the robe on King Charles before he was crowned with the St. Edward's Crown.

Following the crowning, Prince William knelt before his father, placed his hand in his and delivered his allegiance to the monarch. Then he kissed his cheek, prompting the King to respond, "Thank you, William."