Country star Luke Bryan opened up for the first time about the tragic death of his sister Kelly. The family has never revealed her cause of death until now. Bryan spoke to Anderson Cooper on his CNN podcast "All There Is," where Cooper talked to celebrities about losing loved ones. Bryan said Kelly died of Sudden Death Syndrome. Kelly died in 2007 but it's only now that the singer, who is a judge on "American Idol," says he is able to talk about her death. #LukeBryan | Inside Edition