Simplify the following text for a Grade 5 native English-speaking person.
Original: Jennings escaped death in the February 3 , 1959 , plane crash that took the lives of Buddy Holly , Ritchie Valens , and J.P. `` The Big Bopper '' Richardson , when he gave up his seat to Richardson who had been sick with the flu .
Simplified: Jennings first became famous as a member of Buddy Holly 's backing band . On February 3 , 1959 , while playing shows with Holly , he gave up his airplane seat J. P. `` The Big Bopper '' Richardson .