Kate’s wedding dress is iconic – and there’s even more to it than meets the eye.

In celebration of their 13th anniversary, Prince William and Princess Kate have released a never-before-seen photo from their wedding day. It shows William proudly standing with his arms around his new wife, who is every inch the blushing bride in her satin and lace gown.

But did you know that Kate’s dress actually had to be padded out – and also contained a secret message? The future Princess wanted to wear something that combined tradition and modernity, and ended up choosing a timeless vintage style corset dress created by Sarah Burton for Alexander McQueen.

Given Kate’s slender figure, it was decided that in order to create a more dramatic shape, the waist of the dress would be narrowed in, while the hips and bottom were actually padded out to adjust the silhouette.

At the time, the Palace explained: “The ivory satin bodice, which is narrowed at the waist and padded at the hips, draws on the Victorian tradition of corsetry and is a hallmark of Alexander McQueen’s designs.”

The beautiful gown also contained a secret. To give Kate her ‘something blue’, the team secretly stitched a small blue ribbon into the interior of the dress. Her ‘something borrowed’ was the Queen’s Cartier tiara, her ‘something old’ was the lace in her dress and her ‘something new’ was custom-made Robinson Pelham earrings from her parents Michael and Carole Middleton.

Meanwhile, the intricate lace appliqué on the gown actually featured hand-cut individual flowers, incorporating the rose, thistle, daffodil and shamrock to symbolise England, Scotland, Wales and Northern Ireland.

Since their wedding at Westminster Abbey on 29 April 2011, William and Kate have welcomed three children – Prince George, 10, Princess Charlotte, who turns nine on 2 May, and six-year-old Prince Louis.

Alongside the black and white photo to mark their anniversary, the couple simply wrote “13 years ago today!” and tagged the photographer, Millie Pilkington. Millie also shared the image on her Instagram account and wrote: “Happy wedding anniversary! Can’t believe it’s been 13 years. Remember this moment so well. Sending you both much love on this special day.”

The celebration comes at a difficult time for the couple amid Kate’s ongoing chemotherapy following a cancer diagnosis.

William is currently on a reduced schedule from royal duties to support his wife and their three children, who recently returned back to school after a quiet family Easter break.

Kate previously praised her husband for his support in an emotional message to the nation last month announcing her health news, saying it had been “an incredibly tough couple of months for our entire family”. She added: “Having William by my side is a great source of comfort and reassurance.”

The Princess, 42, told how her diagnosis had come as a huge shock and that she and William “have been doing everything we can to process and manage this privately for the sake of our young family”.

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