Columbine shooting survivor's message of hope: "It will get better"
April 20 marks 20 years since the tragedy at Columbine High School. As we look back, we remember the survivors, who still carry the trauma with them every day. We first met Josh Lapp 20 years ago in an interview with "48 Hours." Now Lapp tells "CBS Sunday Morning" correspondent Lee Cowan how he's managed to move forward with his life.