Prentice's maternal grandfather was the Standard Oil tycoon, John D. Rockefeller (1839–1937).
While attending Yale University, Prentice became a member of the Skull and Bones society[1] and was elected to Phi Beta Kappa.
He worked in Boston for a wholesale hardware firm for four years to make enough money to return to Yale.
In March 1941, before the Japanese attack at Pearl Harbor, Prentice volunteered in the U.S. Army as a private.
Prentice became a cattle breeder and is known as a pioneer of artificial insemination in farm animals as a means of improving their genetic pool.