As she attended the state funeral at Westminster Abbey, the Princess of Wales, 40, had on a black Alexander McQueen coat dress. She paired the look with black suede Gianvito Rossi pumps and a black hat by Philip Treacy, featuring a veil.
Kate previously wore a white version of the Alexander McQueen coat dress during a recent happy time with the Queen — the Trooping of Colour parade in June. This year's Trooping the Colour, the public celebration of the Queen's birthday, was particularly special as it happened during the celebration weekend for the monarch's Platinum Jubilee, marking her historic 70th year on the throne.
Kate, Prince William and their three children joined Queen Elizabeth in the tradition of gathering on the Buckingham Palace balcony to watch airplanes in formation fly overhead.
Princess Kate has often taken fashion cues from the Queen in the past, with garment color being one element that has long tied them together. But two days before Monday's procession, Kate wore a three-strand pearl necklace that belonged to the late monarch at a lunch reception at Buckingham Palace.
The accessory, which was a go-to piece for the Queen, was worn alongside a pair of pearl and diamond earrings, which were also previously owned by the monarch.
Tim Rooke/Shutterstock From left: Meghan Markle, Queen Camilla, Prince George, Kate Middleton and Princess Charlotte
The Queen died on Sept. 8 at her Scottish residence, Balmoral Castle, at age 96. She is Britain's longest-serving monarch, boasting an impressive 70-year reign that began in February 1952.
The monarch's son King Charles III, 73, succeeds her, though his coronation won't commence until sometime next year.
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Charles revealed that Kate's new title is the Princess of Wales, which was previously helmed by Charles' late ex-wife Princess Diana. As for her husband Prince William, he will soon inherit his father's former title, the Prince of Wales.
The longtime couple changed their social media pages to reflect their new titles hours after the Queen's death was announced.
PA Images via Getty Queen Elizabeth II in the Throne room at Buckingham Palace after her Coronation in Westminster Abbey
Princess Charlotte, 7, could potentially inherit the title of Princess Royal, which is currently held by the Queen's only daughter, Princess Anne. This could occur once William, 40, ascends the throne, provided that Anne, 72, is no longer living.
When William becomes King, Prince George, 9, will be granted his father's current title, the Prince of Wales.