Duchess of Cambridge Kate Middleton reportedly once asked her friends via email to stop calling her Kate.
The mum-of-three is said to have told those close to her - in the late '00s when, she was dating Prince William and preparing for her future role as a royal - that she would prefer to be called Catherine.
Writing at the time, as reported by Express, columnist Adam Helliker claimed Kate was taking her part "very seriously".
He wrote: "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.
We were a little surprised about the request to call her Catherine.
"It looks like she's taking it very seriously indeed too. I hear that in the past few weeks the former accessories buyer has quietly informed friends that she would like to drop the informal 'Kate' and in future wishes to be known by her full name: Catherine."
One of her pals reportedly told him: "Everyone knows it's about to happen with Kate and William, but we were a little surprised about the request to call her Catherine."
The request was said to have been made by email, but according to royal expert Daniela Elser, the tone in the newly unearthed documents was "gentle" and "jokey".
As all royal fans know, Catherine didn't stick and it isn't known whether or not the duchess has a problem with people calling her Kate in 2019.
She's come a long way since meeting Prince William. The pair tied the knot in 2011 and have since had three children - Prince George, six, Princess Charlotte, four, and Prince Louis, one.
Last week, Kate and William were at a charity event with George and Charlotte when their daughter got a big laugh from the crowds with her cheeky antics.
The four-year-old was being ushered past a group of onlookers at a regatta event in Cowes, Isle of Wight, when Kate pointed and tried to get her to wave.
But instead, Charlotte decided to stick her tongue out.
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