The Queen paid a touching tribute to her late husband Prince Philip at the Jubilee pageant.
Her Majesty was spotted wearing green, which is the Duke of Edinburgh's favourite colour.
The monarch wore a bright neon green dress to Harry and Meghan's wedding in 2018, Birmingham Live reports.
It was used for his staff liveries - the Duke's page at the coronation wore dark green and silver - and private cars.
Green is the colour most commonly associated with rebirth, renewal and immortality.
It is also seen as the colour of hope and is connected with the colour of springtime.
Princess Eugenie has described the Jubilee Pageant as "incredible". She wrote on her Instagram: "The Platinum Jubilee Pageant was just incredible.
"To all the people that took part, organised it, made it flawless for us all watching, Thank you. You made us all so proud." The Duchess of Cambridge opted for pink at the pageant, wearing a long-sleeved pink dress with ruched front detailing.
Like the Queen and the Duchess of Cornwall, the Countess of Wessex also wore green on Sunday. Sophie wore a green belted jacket over white trousers when she joined thousands of people at a picnic near Windsor Castle.
The Duchess of Cornwall also wore green earlier on Sunday when she attended a Big Jubilee Lunch in south London.
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