Kate Middleton is 30! Look Back at the Duchess' Most Beautiful Outfits Over the Year

Kate Middleton turns 30 years old on January 9, 2012. While it had been initially reported that Prince Harry and little sister Pippa Middleton were planning a big bash to celebrate her milestone day, it sounds like the event was called off. The Duchess of Cambridge may have preferred a quieter celebration now that she's a royal and required to attend so many parties.

Pippa might have been a little disappointed, as she's said to be getting £400,000 to write a book about how to be the perfect hostess, and probably looked forward to showing off her skills for her big sister Kate.

A St James's Palace spokesman said, "Whatever is planned will be low-key and private." We hope she enjoys a little privacy and relaxation on her big day.

In the meantime, let's take a look back at some of the duchess' fashions over the year, and you'll see why she was so deserving of being selected as Britain's Best Dressed by Harper's Bazaar magazine.

Just this Sunday, on the eve of her big 3-0, Middleton and husband Prince William were photographed at as they stepped onto the War Horse red carpet, looking like a scene from a glamorous film. We're always surprised that the stunning princess seems to outdo herself every time she steps out the door.

This time she wore a black lace gown by Alice Temperley with sheer sleeves and a lined bodice, as well as 3/4 length sleeves and sexy v-neck. It looked strikingly similar to her wedding gown and showed off her amazing slim figure, making it obvious she doesn't have a baby bump just yet.

One of our favorite ensembles was her incredible pale blue chiffon gown by British designer Amanda Wakeley. She wowed everyone at while attending her first solo engagement back in October, filling in for her father-in-law, Prince Charles, with only a day's notice.

We loved Kate's elegant red gown. She glows in the rich color, making heads turn. The birthday girl wore the dress as a guest of honor at a fundraising gala evening in aid of one of William's charities in mid-October, showcasing her timeless beauty and charm.

Princess Catherine also looks beautiful in blue. For her engagement photos she donned a royal blue Jersey wrap dress by Issa London and the gown immediately became a piece of fashion history.

Happy birthday, Kate! We hope you have another wonderful year ahead.

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