Sarah Ferguson was pregnant with her second child Princess Eugenie when she attended Princess Diana's distant relative James Spencer-Churchill's wedding.
James, the 12th Duke of Marlborough, married Rebecca Brown at the Church of St Mary Magdalene in Woodstock, Oxfordshire on 24 February 1990, one month before Eugenie was born – but the Duchess of York proved how stylish her maternity wardrobe was by stepping out in the most striking mini dress.
The pregnant royal looked glowing in a black top layered underneath a purple suit that was made up of an oversized jacket that skimmed over her blossoming baby bump, with a matching knee-length skirt. Sarah kept the winter weather at bay with sheer black tights and accessorised with patent kitten heels, a black wide-brim hat and a large scrunchie holding back her fiery ginger hair.
It appears as though the doting mother had left her eldest daughter Princess Beatrice, then eighteen months old, at home for the occasion.
James and Rebecca went on to welcome a son called George, but their marriage ended in divorce in 1998.
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Sarah isn't the only royal to offer up a delightful array of maternitywear hits - take a look at more pregnant royal wedding guest dresses below…
Eugenie was recently spotted attending a friend's wedding in Mayfair alongside her husband Jack Brooksbank looking fabulous in florals. The royal – who is expecting her second child – looked ever-elegant in a ditsy print dress featuring earth-toned blooms with an ethereal pleated skirt, a round neckline and a loose fit, perfect for enhancing her baby bump.
She wore her auburn locks down loose and held firmly in place by a cream-coloured headband, and added a pair of nude point-toe heels and an oatmeal-hued leather handbag.
The Duchess of Sussex may not have announced her pregnancy until a few days later, but she hid her bump at Princess Eugenie's wedding. She was pictured smiling and waving in a midi coat dress with large buttons down the front and a wide fit, concealing the fact that she and Prince Harry were expecting their first child, Archie Harrison.
Ahead of the birth of her daughter Lena in 2018, Zara Tindall also stepped out in a beautiful teal coat dress decorated with black floral embroidery at Prince Harry and Meghan’s wedding. Accessorising to perfection, the royal wore navy heels, a matching box clutch and a rose-embellished statement hat, which she styled with her hair in a chic low chignon.
The Princess of Wales donned a bargain black and white polka dot Topshop dress in May 2013, while she was expecting Prince George. She attended William van Cutsem and Rosie Ruck Keene's wedding in the pretty mini dress, which she teamed with a black and white Vivien Sheriff hat and a little black jacket.
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