Kate Middleton wears another blue dress, defo her favourite colour

Kate Middleton has worn a dazzling array of outfits since she became a member of the Royal Family, but we are definitely sensing a theme.

Kate Middleton in blue dressKate Middleton in her blue dress today. Copyright [Rex]Today, Kate Middleton has stepped out in a gorgeous blue dress - the latest in a long line of blue frocks she's been spotted in over the past year.

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The Duchess of Cambridge was visiting the National Portrait Gallery - of which she's a patron - and donned an electric blue shift dress for the occasion.

Kate Middleton in a blue dressKate Middleton kept her look simple, teaming the dress with black heels. Copyright [Rex]Kate kept her look simple, teaming her dress with a pair of black heels and a chain necklace.

However, it's not the first blue outfit we've seen Kate Middleton in. Her famous engagement dress was, fittingly, a sophisticated royal blue.

She also selected various shades of blue for numerous special occasions during her first year as a Duchess.

Kate Middleton in blue dressesKate Middleton has worn blue for her first public appearance, her trip to Canada and for Prince Philip's 90th birthday. …Kate wore blue dresses during her trip to Canada with Prince William last year, as well as for Prince Phillip's 90th birthday and for her first ever public speech back in March. Phew.

Then there's her sapphire engagement ring and the fact that when asked to judge a shoe designer competition, she chose a pair of sky blue stilettos as the winning pair.

So after using all of our best investigative skills, we've decided that Kate Middleton's favourite colour is definitely blue. We feel like we know her a bit better now.