He may have been faced with a difficult dilemma (what do you buy the girl who has everything?) but luckily the Duke has something extra special up his sleeve for the Duchess of Cambridge in 2013: a house.
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.
And he will present the details on her birthday, January 9.
'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.'
Although it was reported Kate's sister Pippa Middleton planned her an eighties-themed birthday bash last year, it's thought this year's celebrations will be much more low-key.
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.'
Yesterday it was revealed Kate Middleton was left without her royal hubby on New Year's Eve, after he was called out on an emergency RAF search and rescue mission.
According to reports, Kate saw in 2013 with her parents instead, while the Duke, known as Flight Lieutenant Wales, joined military colleagues at their Anglesey base to search for a missing man, who was believed to have been swept out to sea while walking his dog.
WATCH: Kate Middleton's best dresses of 2012
What do you of Prince William's birthday treat for Kate Middleton? Let us know in the comments box below…