The Duchess of Cambridge delighted royal watchers with a surprise appearance in a recycled outfit alongside Prince William at an Anzac Day service in London.
The 40-year-old wasn't scheduled to attend the Service of Commemoration and Thanksgiving at Westminster Abbey with her husband but a last-minute diary shift saw her step out at his side on Monday morning.
Dressed in black and white monochrome, Catherine made a sustainable style statement by re-wearing the Alexander McQueen coat dress she previously wore for Princess Charlotte's 2015 christening.
She paired the frock with black pumps, a Jenny Packham clutch and a unique $1,400 halo-style headpiece from Taylor London featuring a coordinating black bow.
A bright red poppy was pinned to her lapel alongside a sparkling diamond brooch, but it was Catherine's earrings that caught the attention of royal fans; they were Princess Diana's iconic Collingwood Pearl Drop Earrings.
The Duchess of Cambridge has donned the set countless times over the years, along with several other signature pieces from the late Princess of Wales' jewellery collection.
Prince William accompanied his wife, having laid a wreath at the Cenotaph in London on behalf of the Queen earlier in the morning.
He included a handwritten note with the wreath, which read: "In memory of those who made the ultimate sacrifice for our freedom. William."
The royal family have marked Anzac Day for over a century, since the reign of King George V who first observed the day in 1916, one year after the Gallipoli landings during WWI.
Prince Charles led the royal tributes this year, saying in a statement: "My great-grandfather, King George V, wrote of the first ANZACs, 'They gave their lives for a supreme cause in gallant comradeship.'
"One hundred and six years later, gallant comradeship remains a defining mark of the uniformed men and women of New Zealand and Australia. Lest we forget."
WATCH: Prince Harry and Kate Middleton arrive for Anzac Day Service in 2019. Story continues after video.
Charles also made a subtle reference to the conflict in Ukraine in his message, which was echoed by the Very Reverend David Hoyle as he led the service Catherine and William attended on Monday.
"We read our history afresh and we are freshly sensitive to what war does. The narratives look a bit less sure, don't they? We feel a bit less confident when violence can be so sudden and political will so arbitrary, so senseless," he said.
"In the foxholes of Anzac cove, the bunkers of shattered cities in Ukraine, in the depths of distancing and isolation in the pandemic, we learn again and again what it is to be thrown back on just our human recourses. The horror builds and you have your humanity or you have the indifferent gods."
The Queen attended Anzac Day services for much of her reign but was unable to attend this year, the 96-year-old monarch scaling back her duties since a recent bout of poor health.
This isn't the first time the Duke and Duchess of Cambridge have paid tribute to the Anzac legacy, sharing a poignant message on April 25 last year to mark the solemn occasion.
"This Anzac Day, Catherine and I join Australians and New Zealanders across the world to remember and honour the service men and women of the Australian and New Zealand Army Corps," they said in a statement last year.
"Today we stand together to reflect not only on their sacrifices, but also their courage, sense of duty, and their famously indomitable spirit."
They recognised Australians and New Zealanders for keeping the legacy alive in modern times, concluding: "The Anzac qualities of endurance, courage, ingenuity, good humour and mateship are admired as fiercely as ever before. Lest we forget."