Sarah Burton Wouldn’t Even Tell Her Own Mother That She Was Designing Kate Middleton’s Royal Wedding Dress, It Was So Top Secret

If you were paying close attention, the day after Sarah Burton announced she would be leaving Alexander McQueen after 26 years with the house, the Princess of Wales stepped out in a navy-blue suit by the label on a royal engagement at a men’s prison. Her choice of outfit was believed by many to be a silent, subtle—but received—message of thanks to Burton, who designed the then Kate Middleton’s 2011 wedding dress, a dress that launched both women into new levels of their lives.

Of the navy-blue suit, by the way: Kate owns the look—a blazer and cigarette pants—in a number of colors, including black, white, and Barbie pink. Alexander McQueen is one of the top labels Kate gravitates towards over and over, not just for her wedding 12 years ago, but every year since.

Burton’s career is far more than just one dress, but, as Kate’s wedding dress is one of the most iconic pieces of all time, it definitely is what Burton is most known for, particularly outside of fashion circles. Per The Daily Mail, Kate is believed to have chosen Sarah Burton to create the dress anticipated around the world after being impressed by the Alexander McQueen gown that fashion journalist Sara Buys wore when she married Tom Parker-Bowles in 2005. (Parker-Bowles, of course, is the son of the then Camilla Parker-Bowles, who also married that year, to Prince Charles; she is now Queen.)

“Miss Middleton chose British brand Alexander McQueen for the beauty of its craftmanship,” the Palace said in a statement at the time of the wedding.

According to Burton, the gown was a 50/50 collaboration between herself and Kate, who herself was inspired by actress Grace Kelly’s 1956 wedding dress when she wed Prince Rainier of Monaco. Kate visited the “Grace Kelly—Style Icon” exhibition at the Victoria & Albert Museum the year before her wedding, “and fashion pundits noticed parallels between the two gowns,” The Daily Mail writes.

Kate’s dress—which featured a Victorian-style corset (which narrowed at the waist and was padded at the hips) underneath a lace bodice—was such a closely guarded secret that Burton didn’t even tell her mother what she was working on. “Even my mum called me and asked me, ‘You wouldn’t tell me, would you?’” Burton said after the April 29 wedding.

The lace on the gown was created by the Royal School of Needlework, which cut individual flowers (rose, thistle, daffodil, and shamrock) from antique lace and appliqued them onto ivory silk tulle. “We knew who it was for, but it was very secret,” said embroiderer Amanda Ewing, who was part of the team who made the dress. “We had net curtains up, and cleaners were not allowed into the room, and the code on the door was changed.”

Kate paired her dress with the 1936 Cartier Halo tiara, on loan from Queen Elizabeth (one hell of a something borrowed) and her something new was a pair of diamond earrings given to her by her parents, Michael and Carole Middleton. The earrings echo the Middleton family coat of arms and were shaped like oak leaves with a pavé diamond acorn suspended in the middle. Kate’s wedding shoes—size five and a half—were made of ivory duchesse satin and adorned with lace; like the gown, the shoes, too, were crafted by the team at Alexander McQueen.

“The dress is classic and goes very well in the Westminster décor,” the late Karl Lagerfeld said at the time of the wedding. “It almost reminds me of [Queen] Elizabeth’s wedding, the royal weddings in the ‘50s.” (Well, Her late Majesty married in 1947, but close enough.)

Per The Daily Mail, Burton joined McQueen straight out of college in 1997. The first question Lee—as McQueen was known—asked Burton was “Do you believe in UFOs?” The pair worked together for 13 years before Lee’s suicide in February 2010; after that, Burton “reluctantly took over the helm,” The Daily Mail writes.