The Duchess of Cambridge carried out a rare joint outing with the Prince of Wales and the Duchess of Cornwall last week, and royal fans have since noticed something striking about Kate's outfit choice for the engagement.
The trio visited The Prince's Foundation's Trinity Buoy Wharf, a training site for arts and culture on Thursday, and the Duchess of Cambridge looked stunning in a repeat grey Catherine Walker coat dress.
The first time Kate ever wore the ensemble was to accompany the Queen on a visit to King's College London in 2019, and the outfit got another rework last week, just days before Her Majesty made an announcement about the Duchess of Cornwall's future title.
WATCH: Kate joins Charles and Camilla for rare outing in London
In remarks to mark the 70th year of her reign, the Queen said: "I remain eternally grateful for, and humbled by, the loyalty and affection that you continue to give me. And when, in the fullness of time, my son Charles becomes King, I know you will give him and his wife Camilla the same support that you have given me; and it is my sincere wish that, when that time comes, Camilla will be known as Queen Consort as she continues her own loyal service."
Kate first wore the Catherine Walker dress for an outing with the Queen in 2019
One royal fan commented on Instagram: "Does this mean that Kate made the appearance and wore the grey dress again with Camilla that she last wore with the Queen to a very subtle hint at the announcement about Camilla being Queen Consort?"
MORE: The Queen hosts tea party as she prepares to make history
Kate wearing an Orla Kiely dress for an outing with Charles and Camilla in 2012
Other social media users have noticed that the Duchess of Cambridge often wears neutral outfits when in the presence of more senior members of the royal family.
"I wonder if Catherine deliberately wore a simple, neutral outfit to allow Camilla to shine with that wonderful green and peplum outfit. It's a milestone engagement regardless," one wrote. Another added: "It's not the first time she's worn grey with Camilla and Charles. And the first time she wore this coat was when she accompanied the Queen on an engagement. I don't think it's a coincidence if that makes sense."
On a joint outing with Charles and Camilla to the Dulwich Picture Gallery in 2012, Kate also opted for a pleated grey Orla Kiely dress.
It's also common for the royal family to wear outfits in complementary hues, such as Royal Ascot in 2019, with the Queen, Kate, Princess Beatrice, Princess Eugenie and Zara Tindall all wearing dresses in shades of blue.
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