Kate Middleton

William and Kate will leave Sandringham in the next 48 hours and travel to Bucklebury in Berkshire for the big night.

After spending Christmas with the Queen and the rest of the royals in Norfolk, the couple decided they wanted to celebrate the passing of 2013 with the "amazingly supportive" Middleton family.

Last year William and Kate broke with tradition and spent Christmas Day with her parents before travelling to Sandringham.

There had been reports that Michael and Carole Middleton had been invited to the annual Boxing Day shoot but, with Sandringham crammed to the rafters with up to 30 royals, that was a non-starter.

"William and Kate are just like any normal couple and want to spend time with both families," said a friend of the pair last night. "It's a situation that millions can identify with, and obviously you can't be in two places at once.

"So this year they are reversing it and seeing in 2014 with Catherine's family.

"They have been amazingly supportive in the past couple of years and of course they are doting grandparents to George.

"William likes being at Sandringham, but he also loves the informality of staying with Kate's parents and just chilling out in a normal family environment."

Kate's sister Pippa and brother James will also be at the Middleton's £5million seven bedroom house, which they bought last year.

It is thought Pippa's boyfriend Nico Jackson and James's girlfriend Donna Air have also been invited.

"It's going to be a lively night with a great party atmosphere," said the friend. "The Middletons are always great hosts and like guests to enjoy themselves."

In future years, when Wills and Kate have Anmer Hall as their home on the Sandringham estate, it is thought that the Middletons could join them there.

Meanwhile, Prince Harry's girlfriend Cressida Bonas has reportedly flown to the Caribbean to spend the New Year on Sir Richard Branson's Necker Island hideaway in the Virgin Islands.

Despite increasing speculation, friends say it is too early to say if Harry, 30, and Cressida, 24, will get engaged next year.