Princess Eugenie was pictured in a pretty A-line dress just hours before attending her grandmother the Queen's Birthday Parade, where she put in a low-key appearance and remained undetected by cameras.
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The 32-year-old daughter of Prince Andrew and Sarah Ferguson looked elegant in a Palmer Harding dress to attend the opening of Horatio's Garden at The Royal National Orthopedic Hospital on Wednesday. Eugenie's 'April Shirt Dress' in navy boasted a button-down front, cinched in waistline and above-the-knee cut, and she teamed the understated number with a coordinating pair of Jimmy Choo 'Romy 85 Navy Suede Pumps'.
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Princess Beatrice's younger sister looked fresh-faced and radiant for the event, which was a cause close to the scoliosis sufferer's heart.
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Taking to Instagram to explain her involvement with the initiative, she wrote: "What a joy it was to officially open the new @horatiosgarden at The Royal National Orthopaedic Hospital. This is their 5th garden in the UK connected to a spinal unit offering patients nature and the outdoors at a time they need it most.
Princess Eugenie looked beautiful in an A-line mini dress
"I'm a proud patron of this charity and it was a particularly special visit as it's the hospital I underwent spinal surgery as a child. It was an honour to meet all the volunteers, doctors, nurses, patients and gardeners who really bring this garden alive."
Royal fans were hoping to catch a glimpse of Princess Eugenie at the Trooping the Colour celebrations. However, the princess flew completely under the radar and wasn't photographed at the event.
Eugenie, her husband Jack Brooksbank, sister Princess Beatrice, cousin Prince Harry and his wife Meghan Markle didn't make an appearance on the Buckingham Palace balcony this year, with only senior working royals taking centre stage alongside the Queen.
Princess Beatrice was pictured at the event, however, peering out from one of the windows with young royals including Prince George and Mia Tindall.
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Sharing a sweet tribute to her grandmother the Queen just before Trooping the Colour began, Eugenie told royal fans: "Her Majesty the Queen is an incomparable monarch who has reached a record-breaking milestone.
Princess Eugenie was elegantly clad in a Palmer Harding dress
"She also happens to be my grannie, and I am a very proud granddaughter."
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This marked the second outing of the day for Eugenie, who also paid a visit to London's V&A museum wearing a stunning constellation dress, a gorgeous past-season buy from Whistles.
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