1957: Ricky Nelson released his first single "Teenager's Romance" on Verve Records. (Note: some websites claim the song was released April 27. We know that Ricky made his musical debut on April 10 before the single was released, and it debuted on the charts on May 13. According to 'United Press International', Ricky released the single on April 24.)
1958: After an earlier release on Mohawk Records failed, Dion & the Belmonts switched to Laurie Records and released the single I Wonder Why". (Note: some websites say the song was his first single release, ignoring the release on Mohawk. Others say the song was released May 5. According to 'United Press International', the song was released on April 24.)
1959: Buddy Holly hit #1 on the U.K. Singles chart six weeks after his death with the Paul Anka song "It Doesn't Matter Anymore".