Prince William's girlfriend Princess Kate parties in sheer wedding guest dress in unearthed photos

Before marrying Prince William, Princess Kate (nee Middleton) had already begun mingling with her future royal in-laws, including attending high-profile weddings without her then-boyfriend.

While the Prince of Wales was visiting Kenya, where he attended his ex-girlfriend Jecca Craig's wedding, Kate joined the likes of Prince Harry and Chelsy Davy to celebrate Peter Phillips and his ex-wife Autumn Kelly's nuptials at St. George's Chapel on 17 May 2008.

In unearthed pictures shared exclusively with HELLO! magazine, Princess Kate arrived for the ceremony in a black knee-length dress layered underneath a pastel pink corset-style lace-up jacket.

She teamed her outfit with a pink satin box clutch by Prada and a black fascinator with a birdcage veil placed atop her bouncy curls. While the top of Kate's sheer wedding guest dress was just visible peeking out from underneath her jacket in the afternoon, fans got a better glimpse of the frock at the evening reception as she hit the dancefloor.

With its thin mesh back, cutout sides and illusion neckline, it was certainly a daring choice by royal standards. The frock was designed by Issa, which happened to be the brand Kate turned to for her elegant navy engagement dress two years later.

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The Princess of Wales attended a photocall in November 2010 in the wrapover frock which perfectly matched her sapphire and diamond engagement ring, which belonged to William's late mother Princess Diana. He had proposed during a trip to Kenya with friends but admitted he had carried the ring around for three weeks before finding the perfect moment to pop the question.

During their engagement interview with journalist Tom Bradby, William admitted he feared how Kate's family would react to his proposal. "Well, I was torn between asking Kate's dad first and then the realisation that he might actually say 'no' dawned upon me.

"So I thought if I ask Kate first then he can't really say no. So I did it that way round," he said, adding: "I managed to speak to Mike soon after it happened really and then it sort of happened from there."

However, William's family had no reservations about Kate, whose first interaction with the late Queen Elizabeth took place at Peter and Autumn's wedding – without her then-boyfriend.

Prince William explained of his late grandmother: "She's very welcoming. She knew it was a big day and everything was going on with Peter and Autumn were there and things and she'd wanted to meet Kate for a while so it was very nice of her to come over and say hello."

The Prince and Princess of Wales recently celebrated their 13th wedding anniversary after tying the knot at Westminster Abbey in April 2011.

Among the 2,000 guests witnessing the ceremony was William's brother Prince Harry, who appeared to be William's best man, father Prince Charles and grandmother the late Queen, while Kate was supported by her parents Carole and Michael Middleton, brother James and bridesmaid Pippa Middleton.

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