She’s a natural at royal engagements and has always proved to be one of the most popular members of the Windsor household—but Kate Middleton’s easy charm with the public came as a result of advice from an important mentor.

When Kate, who was just 19-years-old when she first met her future husband Prince William at St Andrew’s University, officially joined the royal fold, it was Prince Philip who took her under his wing.

The Duke of Edinburgh imparted a very important royal rule that Kate has reportedly taken to heart—and it has helped her on every public-facing engagement since.

In a 2021 biography about the late royal titled Philip: The Final Portrait, journalist and author Giles Brandreth said that Philip shared his “golden rule” for navigating life in the spotlight.

london, england june 17: (l r) queen elizabeth ii, prince philip, duke of edinburgh, catherine, duchess of cambridge, princess charlotte of cambridge, prince george of cambridge and prince william, duke of cambridge look out from the balcony of buckingham palace during the trooping the colour parade on june 17, 2017 in london, england. (photo by chris jackson/getty images)
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Brandreth reported that Philip told the future Princess of Wales: “If you think the attention is on you personally, you’ll end up in trouble... The focus is on your role, what you do, what you support. It’s not focused on you as an individual. You’re not a celebrity. You represent the royal family.”

The late Duke also told Kate to not look at the numerous flashing cameras who will be trying to get photos of her every move. Instead, Philip reportedly told Kate to look only at the people they were there to see, to ensure they felt seen and acknowledged.

Brandreth continued: “I have been on walkabouts with [Princess Kate]. She does not look at the camera. Whenever she is interviewed, Catherine talks about the matter at hand, never about herself.”

london, united kingdom june 12: (embargoed for publication in uk newspapers until 48 hours after create date and time) catherine, duchess of cambridge and prince philip, duke of edinburgh watch a carnival parade as they attend the patrons lunch celebrations to mark queen elizabeth iis 90th birthday on the mall on june 12, 2016 in london, england. (photo by max mumby/indigo/getty images)
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Kate took some time out of the public eye last year, as she underwent medical treatment for a cancer diagnosis. She has since returned to the usual roster of royal engagements (and even debuted a sunny, blonder hairstyle in more recent weeks while out and about).

Kate’s most recent visit to the public was alongside Prince William, with the pair attending the Women’s Institute in Windsor to mark the three-year anniversary since Queen Elizabeth II passed away.

prince william and kate
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The Wales family themselves are set to be very busy over the next few weeks, as it has been reported the family of five are moving to Forest Lodge in Windsor Great Park. Royal sources have described the move as a “fresh start,” with Kate and William hoping this can be their “forever home.”