Pippa Middleton And Ashton Kutcher Among Stars Invited To Princess Beatrice's 25th Party

Plans are under way for Princess Beatrice's very special 25th birthday tomorrow

Princess Beatrice, who turns 25 tomorrow, is planning a 'sporty' birthday bash for her star-studded guest list at Royal Lodge in Windsor Great Park tomorrow.

Robbie Williams, Sir Richard Branson and Dizzee Rascal are among the mixed bag of stars expected at the 100-strong bash, and they have all been told to bring trainers, an insider tells the Mail Online.

‘Guests have been told to bring trainers as the agenda for the evening involves outdoor games, followed by a big dinner,’ the source explains.

While activity has been hinted for the evening, Princess Eugenie and Sarah Ferguson have been enlisted to plan the party and so enforced a further Argentina theme.

Her trusted mother and sister chose to draw upon Eugenie's love of sport, following her London marathon run in 2010, combined with her love of the country she visited on her gap year.

Dancing on tables and hopefully showing the Princess how to party like the fourth-in-line to the throne, Prince Harry is expected to make her royal acquaintance alongside Pippa Middleton, attending in the absence of her sister Kate, while she looks after the newborn and Prince William returns to work.

Other guests on the list include Ashton Kutcher, who attended the royal's 18th birthday bash in 2008 with his then-wife, Demi Moore.

Princess Beatrice's 18th birthday was a equally extravagant masquerade ball, which featured a strange mix of youth culture and royal tradition including rap music from 50 cent and end-of-the-night bacon butties hand-delivered by the Queen's servicemen.

She wore a £10,000 Marchesa dress sourced from New York, as a gift from the Queen.

Princess Beatrice may have sourced her 25th birthday dress from any one of the holiday destinations she's enjoyed in recent months, including St Tropez– where she holidayed with Ashton Kutcher and Mila Kunis – or Venice, where she spent time with Kate Moss.

Princess Eugenie never fails to surprise us with her utterly fabulous famous friendship list so we can't wait to see who else received the royal invite. Umm, where was ours?

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