Prince William & Duchess Kate: 'War Horse' UK Premiere.

Sun. Jan. 8, 2012

Having wowed in Alice Temperley at the War Horse premiere last night, Kate Middleton hits a birthday milestone today in turning 30

Marry a prince, travel the world, become a fashion icon, do more charity work. If this was Kate Middleton's to-do list before she turned thirty, she can consider it done. On Monday, the Duchess celebrated the big three-oh without any of the sloppy, liquid-courage fanfare that usually comes with crossing the milestone. 

Instead she toasted her accomplishments at a low-key dinner with her nearest and dearest.

 Catherine, Duchess of Cambridge, turns 30 Monday amidst excited buzz about what husband Prince William of Wales will give her, and how she will celebrate — a big bash (sis Pippa is a party-planner) or a low-key private party? According to the U.K.'s Daily Mail, William, who turns 30 in June, is said to be buying his bride a new watch and commissioning an oil portrait of her. His grandmother Queen Elizabeth II supposedly is giving her a tiara from the royal collection. In honor of the Duchess' big day, here are 30 reasons why we can't get enough of Kate.

"[She] had a quiet gathering with family and friends on Monday evening," a Palace aide told Us Weekly. "The dinner was held within private quarters at one of the properties situated by their home at Kensington Palace." 

Sister Pippa and brother-in-law Harry were both rumored to be planning an all out rager for Kate, but according to The Daily Mirror, it was Guy Pelly, the nightclub owner and close friend of the royal couple, who arranged a more subdued evening centered on a multi-course meal prepared by one of Kate's favorite chefs.

So the party wasn't exactly a three-day marathon as is custom for Middleton's fellow countrymen ('ello Kate Moss and Naomi Campbell). As a future Queen, Kate's grown up faster than most in the final chapter of her '20s. Now she's poised to begin philanthropic work for a number of charities, in addition to playing unofficial ambassador for her native land.

It wouldn't be proper to wave around the spoils of her birthday, but rest assured there were spoils.

The Duke and Duchess of Cambridge arrives for the UK Premiere of 'War Horse' in aid of The Foundation of Prince William and Prince Harry, at a central London cinema, London, Sunday, Jan. 8, 2012. (AP / Ian Gavan).

Prince William's wife, who turned 30 today, celebrated her birthday at the film premiere of Steven Spielberg's War Horse, where she disappointed baby-bump watchers thanks to another slim-fitting, floor-sweeping gown from one of her go-to British designers, Alice Temperley.

Happy Birthday! Kate Middleton turns 30 today.

The Duchess of Cambridge talks to a guest after being presented with her bouquet as she arrives for the UK Premiere of 'War Horse' in aid of The Foundation of Prince William and Prince Harry, at a central London cinema, London.