No bride wants to be upstaged on her wedding day. It takes a very brave bride, then, to invite a duchess to her wedding, especially when the duchess, in this case, Kate Middleton, made headlines around the world for her own royal, fairy-tale wedding.

But there was Middleton, the Duchess of Cambridge, sitting among the guests at the weekend wedding of a close family friend in Oxfordshire, England.

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The bride, Thierry Kelaart, is a close friend of sister Pippa Middleton's who attended school with her and whose family lives in a village neighboring Bucklebury, where the Middletons have their family home. Kelaart even chose Middleton's father, Michael Middleton, to walk her down the aisle because her own father died almost 20 years ago, according to the UK's Daily Mail.

Kate Middleton, 30, attended the nuptials stag, without her husband of 18 months, Prince William, who was reportedly at home in Angelesy, Wales, fulfilling his duties as a search-and-rescue pilot with the Royal Air Force (RAF). Instead, Middleton was surrounded by her family, including her sister, Pippa, and mother, Carole Middleton, in addition to her father.

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Despite the high-wattage royal guest list, the wedding was reportedly a quiet affair that included an hour-long ceremony in St. Bartholomew's Church in Oxfordshire followed by a small reception.

In her first public appearance since returning from an official overseas trip to Asia with Prince William, Middleton wore a light-blue dress by Erdem, accessorized with a trademark fascinator. The Erdem dress is the same one the duchess wore in June while attending festivities to mark the Queen's Diamond Jubilee in London.

Middleton's smiling face alongside her family showed no signs of strain from the topless photo scandal that struck while the couple was in Asia and expanded over the weekend when a Danish magazine reportedly published even more revealing photos of the duchess sunbathing while at a private chateau in France with William. Police in France, at the request of the royal family, have opened a criminal investigation into whether the photos were an invasion of privacy.