Robert Pattinson celebrated his 26th birthday at Claridge's hotel in London this evening. He played host to friends like Hugh Jackman and a pregnant Sienna Miller. It was back to the city for Robert after he spent the weekend with Kristen Stewart in the English countryside, where she was busy with press duties for Snow White and the Huntsman. The duo stayed together at the Bailiffscourt Hotel in West Sussex, England, a spot just 15 minutes from Kristen's work duties at Arundel Castle. The last week has been extrabusy for Kristen. She jetted to Paris for a round of interviews on behalf of her new movie, which is out on June 1, before moving on to the UK.