Girard Henderson (Jerry) was born on February 25, 1905, in Brooklyn, New York. He was the son of Alexander D. Henderson and Ella M. Brown. He was the grandson of Joseph Henderson (pilot) and brother to Alexander D. Henderson, Jr. In 1910, the family moved from Brooklyn to Suffern, New York. Henderson went to the Suffern Grammar School and later the Sisters of the Holy Child Jesus. He continued his education at the preparatory Storm King School in Cornwall On Hudson, New York. He graduated in the class of 1923. In 1925, Henderson was accepted to Dartmouth College, but only attended his freshman year.