FREED Amanda Knox was all smiles as she arrived at an Italian airport to fly home today after four years in prison. Knox looked happier than ever as she arrived at Leonardo Da Vinci airport to fly back to her home in Seattle. The 24-year-old was last night sensationally freed from prison following the decision by an appeal court to overturn her conviction. Her lawyer Carlo Dalla Vedova said today: \"I spoke with her briefly. She was calm, serene and looking forward to going home and just spending time with her friends and family. She wants to get on with her life. \"She is a clever and intelligent girl who has been through a lot - one day in prison is bad enough but four years is even worse.\"Knox had been serving a 26-year prison sentence after being found guilty in 2009 of the brutal murder of Meredith Kercher, 21, who was found semi-naked with her throat cut in her bedroom of the house they shared in Perugia, ­Italy. The court case has gripped public attention on both sides of the Atlantic as Knox made a sensational and emotional appeal for freedom. Airport officials said she and her family left Italy for London, where they were due to board a connecting flight to their hometown.Meanwhile the Kercher family reacted to the news of Knox and her former boyfriend Sollecito\'s acquittal. Her family said their ordeal would not end until they found out the truth about Meredith\'s murder. Stephanie Kercher, Meredith\'s sister, said they would first wait for the court\'s written explanation of Monday\'s verdict.\"Once we\'ve got the reasons behind the decisions for this one, then we can understand why they have been acquitted of it and work towards finding those who are responsible,\" she told a news conference. \"That\'s the biggest disappointment, not knowing still and knowing that there is someone or people out there who have done this,\" she said.    The acquittal of Knox and Sollecito leaves Rudy Guede, an Ivorian drifter and drug dealer, as the only person convicted of the killing which investigators believe was committed by more than one person.Kercher\'s body, with more than 40 wounds and a deep gash in her throat, was found in 2007 in the apartment she shared with U.S. student Knox in the Umbrian hill town of Perugia, where both were studying.    DNA evidence used to convict Knox and Sollecito was discredited by experts but questions remain over who, other than Guede, was involved in the attack in which Kercher was pinned down and stabbed.