"Their Hearts Were Full of Spring" is a song written by Bobby Troup.
[1] It has been recorded by many artists including Jimmie Rodgers, the Four Freshmen, the Lettermen, the Beach Boys, Sue Raney, the Cyrkle, and Tatsuro Yamashita.
The song was a favorite of American rock band the Beach Boys.
Throughout their career, they performed it regularly, taking the song's vocal arrangement from the Four Freshmen.
[2] In 1963, they released their own version with revised lyrics by Mike Love as "A Young Man is Gone" in tribute to actor James Dean.