HARRY Styles spent his 19th birthday with one surprising guest – his ex-Caroline Flack. The youngest member of One Direction, who turned 19 today, partied at London’s Groucho Club last night with the 33-year-old TV presenter and his close mates James Corden and Nick Grimshaw. The Xtra Factor presenter, who turned up with a friend, made sure all eyes were on her with a red fur jacket and some unusual futuristic heels. The boys started the night by filling up on dinner at a Mexican restaurant, then met up with Caroline inside the member’s club to continue the party. Next stop were two bars in Soho where Harry partied until 4am before heading back to his pad. Ladies’ man Harry and Caroline have been close since they dated for three-months when he was 17 with Caroline describing him as "brilliant and so much fun.” The popular youngster has a surprisingly long list of admirers – including philosopher and all-round serious bloke Alain De Botton. The writer revealed he’s been hanging out with Harry by tweeting a photo of the pair alongside Jemima Khan in the early hours of Thursday morning. He wrote alongside the snap: "We talk Plato, Aristotle, love and beauty.” Quizzed later on the 1D star’s deep thinking, Alain said: "Reports of the death of culture in the young are much exaggerated; Harry is a real enthusiast of Greek philosophy.”