Kate Middleton to mark 31st birthday with 'private' celebration

Pregnant Kate Middleton will celebrate her 31st birthday with a low-key, 'private' 'do, according to a spokesman

Kate Middleton celebrates her 31st birthday today, and will spend it 'privately' at home, according to a spokesman at St James's Palace.

Only her second birthday as part of the royal family, it also marks another year in the pregnant Duchess of Cambridge's royal calendar.

KATE MIDDLETON CELEBRATES WITH TRIP TO CIRQUE DU SOLEIL

And what a year it has been. Since her 30th birthday, Kate Middleton has well and truly immersed herself into the duties of a royal, flitting from official engagement to royal appearance, still finding time to do her own shopping, volunteer at Cub Scouts and keep her charity work on the go.

This year, Kate gave a rare insight into her relationship with Prince William, revealing she missed him 'terribly' as he left her at home and undertook a royal tour of duty in the Falklands.

Proving the Duchess has well and truly been accepted into the family, the Queen invited William and Kate to travel on the royal barge during her Diamond Jubilee pageant in April (who could forget that red McQueen dress?!) and then there was the very public display of affection with Prince William as British Athletes powered home to a gold medal during the Olympics.

Kate gracefully negotiating a schedule of packed engagements during her September Diamond Jubilee tour in the far east, even as topless pictures of her on holiday with Prince William emerged.

And the royal couple proved they were not to be messed with, as Prince William instructed aggressive legal proceedings against the French edition of Closer, who published the intimate pictures of his wife.

On a beauty note, Kate chose 2012 to try a new 'do, showing off off a darker version of her trademark glossy locks and a soft, feathery fringe. While, here at MC, we're huge fans of the Duchess's face-framing new hairstyle, she later confessed she was 'not sure' about the new 'do.

And how could we miss the dresses? From her sweeping white Roland Mouret gown to her lacy Temperley number and a pitch-perfect tour wardrobe, Kate has had some real style highs this year.

Finally, there's the royal baby to look forward to - and by this time year, pregnant Kate Middleton will have a tiny royal son or daughter to look after.

So how will Kate celebrate her landmark birthday?

Insiders say the Duchess is hoping to celebrate with a small family lunch or dinner, and enjoy her last birthday with Prince William, before they welcome their first child into the world.

'Wills and the Middleton family are planning a very quiet do, but there'll be a 'surprise element', which could be one of two things,' the source continued.

'They'll arrange a very small lunch with present openings if she's feeling up to it. Or, they'll throw a big family dinner in the evening.

'She'll just want to be with her family and enjoy her last birthday with Wills before there's a little one to look after. And it seems Kate is just looking forward to spending her birthday with her family before she gets to grip with motherhood.'

A spokesman at St James's Palace simply said the Duchess will be marking her birthday 'privately'. And as far as gifts are concerned?

It's thought Prince William is considering splashing out on a posh pad away from London, but closer than their Anglesey home, where Pregnant Kate can hide away from prying eyes.

'They've talked about getting a place where they can get away from it all. And now Wills has narrowed down the list to a few incredible places in Hampshire and Buckinghamshire around the £5 million mark,' one source revealed.

'They don't want to be too close to London as they are already based in Buckingham palace. Wills has gathered together various property details from some high-end retail estates which he will give to her on her birthday.'

Happy Birthday, Kate!

WATCH: Kate Middleton's best moments of 2012

How do you think Kate Middleton will be celebrating her birthday? Let us know in the comments box below…

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