Why Kate Middleton felt responsible for keeping Prince William, Prince Harry united?

Kate Middleton, the Princess of Wales reportedly saw it as her duty to keep peace between brothers Prince William and Prince Harry.

In new royal biography, William and Catherine: The Monarchy's New Era: Inside Story, the author revealed that Kate spent years acting as a mediator between royal brothers.

Russell Myers revealed that she was said to be uniquely positioned to understand their dynamics and tensions.

He wrote, "Her upbringing in a close-knit, loving family environment, where supporting each other was almost an unofficial family motto, spurred her actions."

"Whether counseling William or having a quiet word in Harry’s ear, she saw it as her duty to keep the two brothers on the same team, as did their senior aides," Russell added.

Previously, Katie Nicholl also told ET! that Kate Middleton acted as peacemaker between Prince William and Prince Harry.

She said, "It’s always been my understanding that behind the scenes, Kate has tried very hard to forge a rapprochement and act as a peacemaker between William and Harry."

"She loves Harry. She says that she is the sister that he never had. She has been heartbroken to see them fall out, and I think she is one of the few people, one of the few family members, who would actually be able to push the brothers together—which she did in a very subtle way, but was very effective," Katie added.