From the surprise private ceremony to the dress, Princess Beatrice and Edoardo Mapelli Mozzi’s royal wedding on Friday was truly unique.

The bride, 31, walked down the aisle on the arm of her father, Prince Andrew — who was not included in any of the day’s official photos — wearing a vintage ivory Peau De Soie taffeta dress borrowed from her grandmother, the Queen, who first wore it back in 1961.

Designed by Norman Hartnell, the gown features sparkling diamanté embellishment throughout the bodice and down the skirt, and got a few major updates before Beatrice’s big day. With the help of the Queen’s dressmaker Angela Kelly and designer Stewart Parvin, much of the volume was stripped from the skirt for a sleeker, more modern look.

Princess Beatrice and Edoardo Mapelli Mozzi on their wedding day

Benjamin Wheeler via Getty Image

Princess Beatrice and Edoardo Mapelli Mozzi on their wedding day

Benjamin Wheeler via Getty Image

Prince Philip and Queen Elizabeth II with Princess Beatrice and Edoardo Mapelli Mozzi on their wedding day

Benjamin Wheeler via Getty Image

Edoardo Mapelli Mozzi and Princess Beatrice on their wedding day

Benjamin Wheeler via Getty Image

Princess Beatrice also had sheer organza puff sleeves added to the dress, which was originally sleeveless — likely to make it more appropriate for a chapel wedding, although some royal fans speculated that the special touch might also have been a nod to the bride’s mother, Sarah Ferguson, who also wore a puff-sleeved gown on her wedding day.

Princess Beatrice’s dress couldn’t have been more different from those worn by her younger sister Eugenie and cousins Meghan Markle and Kate Middleton on their big days. All three of the other royals opted for long sleeves as opposed to short, and only Beatrice selected a dress with embellishment — a rarity among royal brides, who tend to go more conservative with their wedding looks.

What’s more, while Beatrice went the “something borrowed” route with her gown, Eugenie, Meghan and Kate all had their dresses custom-made.

Eugenie, 30, who married Jack Brooksbank in October 2018, commissioned a look from British label Peter Pilotto that dipped low in the back to show off her scoliosis scar. It also featured a wide V neckline, draped collar and a large bow in the back that led into an elegant train; in a departure from typical royal-bride style, she skipped the veil.

Markle, 38, also chose a wedding dress with an open neckline when she said “I do” to Prince Harry in May 2018. Designed by Givenchy’s Clare Waight Keller, her gown was the picture of simplicity; most of the intricate design details appeared on her five-meter-long veil, which was hand-embroidered with flora from all 53 countries of the Commonwealth.

And for her wedding to Prince William in April 2011, Middleton, 38, looked perfectly regal in a bespoke white lace gown by Alexander McQueen designer Sarah Burton that featured long sleeves and a sweeping train.

One thing all four royal brides shared on their big days, however, was the honor of borrowing a tiara from the Queen. Middleton wore the Cartier Halo tiara and Markle the Queen Mary diamond bandeau, while Princess Eugenie stood out in the Greville Emerald Kokoshnik tiara.

But Beatrice’s headpiece might just be the most precious of them all: She walked down the aisle in the Queen Mary diamond fringe tiara, the same one her grandmother wore when she wed Prince Philip in 1947.