1960s pop singer Bobby Vee dies of Alzheimer's at 73

Pop idol Bobby Vee, the boyish, grinning 1960s singer whose career was born when he took a Midwestern stage as a teenager to fill in after the 1959 plane crash that killed rock `n' roll stars Buddy Holly, Ritchie Valens and J.P. "The Big Bopper" Richardson, has died. He was 73.