Kate Middleton reportedly became very aware of her new position even before she married Prince William on April 29, 2011.

Columnist Adam Helliker previously told Express that the Duchess of Cambridge wrote an email to her friends jokingly asking them to start calling her Catherine instead of Kate.

“With Prince William’s engagement now a surefire certainty (even Ladbrokes has stopped taking bets on whether it will happen after a flurry of well-placed wagers) there are intriguing signs that Kate Middleton is preparing for her future role. It looks like she’s taking it very seriously indeed,” he said.

Royal expert Daniela Esler confirmed the news by saying that Middleton’s manner of asking her friends to call her Catherine instead of Kate was very gentle. Even though this was the case, some of Prince William’s wife’s pals were surprised to receive the message from her.

“Everyone knows it’s about to happen with Kate and William, but we were a little surprised about the request to call her Catherine. There is a distinct feeling she has started to become very aware of her position,” the mom of three’s friends told Helliker.

The columnist revealed that when Prince George’s mom was studying at Marlborough College, Middleton was referred to as Catherine. But when she was studying at the University of St. Andrews, she became known as Kate.

Prince William and Middleton first met at the University of St. Andrews. And even the Duke of Cambridge used to call his wife Kate when they were still boyfriend and girlfriend. But after they tied the knot, it became more common for Prince William to call Middleton by her real first name.

Following the royal couple’s nuptials, Queen Elizabeth II bestowed on them the official title of Duke and Duchess of Cambridge, which they still use until today. Cambridge is also the surname that their three children, Prince George, Princess Charlotte, and Prince Louis are using.

Kate Middleton Kate Middleton arrives to launch a new national support line at the charity Family Action on Jan. 22, 2019 in Lewisham, England.  Photo: Getty Images/Adrian Dennis