It's not hard to be the perfect mother-of-the-bride. There's one simple rule you should always follow – never, under any circumstances, upstage the bride. Once that's been committed to memory, your next task is to find the perfect mother-of-the-bride outfit. After all, you're one of the key players in your daughter's wedding not to mention the bridal pictures. So spare a thought for the Duchess of York, who's gearing up for the royal wedding of her daughter Princess Eugenie and fiancé Jack Brooksbank this Friday, October 12. Speculation is rife over who will design Princess Eugenie's wedding dress but we're intrigued to see what Sarah Ferguson is going to wear in her role as mother of the bride. And just in case she needs some style inspiration, we've looked back at what other royal mother of the brides have worn to their daughter's big day.

Doria Ragland

As the only member of the Duchess of Sussex's family to attend the royal wedding in May, Meghan's mother looked every inch the part in a mint green Oscar de la Renta suit with matching Stephen Jones hat and heels by Aquazzura.

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Queen Silvia

Perhaps one of the most glamorous MOB outfits was Queen Silvia of Sweden's, who wore the most stunning blush pink lace gown to the wedding of her daughter, the Crown Princess of Victoria. She of course accessorised with the most jaw-dropping crown, but then she is the Queen.

Carole Middleton

Back in 2011 for the royal wedding of the Duke and Duchess of Cambridge, Carole Middleton knew she wouldn't go far wrong with pastel shades, and her classic pale blue Catherine Walker dress and matching coatdress were the perfect mother of the bride outfit for the wedding of the decade. She topped it off with a hat by Jane Corbett.

Camilla Parker-Bowles

Not long after the royal wedding of Kate and William, William's step-mother Camilla Parker-Bowles rose to the occasion for her own daughter's wedding. Wearing a pale green pleated coat dress and matching fascinator, Camilla was a picture of understated elegance for her daughter Laura's wedding to Harry Lopes.

Maria Hellqvist

Prince Carl Philip and Princess Sofia's wedding was a glitzy affair, and mum Maria Hellqvist's gown didn't disappoint; a long, lacy gown in what colour, but royal blue of course.

Princess Anne

Princess Anne shunned the pale shades we're familiar with the usual mother of the bride outfits and wore a more colourful ensemble for the wedding of her daughter Zara Phillips and Mike Tindall – a pleated coral dress with an off-the-shoulder floral jacket.

WATCH: Why Princess Eugenie still can't wear a tiara unlike Kate or Meghan

Princess Margaret

It was a low-key affair for Princess Margaret's daughter Lady Sarah Armstrong-Jones' wedding to Daniel Chatto. Princess Margaret wore the classic mother of the bride uniform; dress, coat and hat in a cornflower blue shade.

Susan Barrantes

Maybe Sarah Ferguson will take inspiration from her own mother, who wore a canary yellow skirt suit to her daughter's wedding. The matching hat was offset with pearls to make for one of the boldest royal MOB outfits we've seen to date.

Frances Shand Kydd

Princess Diana's mother was known for her impeccable dress sense, and her outfit for her daughter's wedding in 1981 was no exception. That periwinkle blue was a masterpiece, right from her hat down to her hemlines. Added ruffles made it an inspiration for fellow MOB's in the eighties.

The Queen

What does the Queen of England wear to her daughter's wedding? A very simple brilliant blue coat dress with diamond-stitching and the most glorious matching hat.

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