Ernest Greppin was born on May 25, 1967, in Boston, Massachusetts. He entered the U.S. Naval Academy in June 1985, and was commissioned an Ensign in the U.S. Navy on May 31, 1989. Ensign Greppin completed his fleet training, and then attended Basic Underwater Demolition/SEAL training at Naval Amphibious Base Coronado, California, from October 1989 to April 1990, followed by Basic Airborne training at Fort Benning, Georgia, in April and May 1990. His first assignment was with SEAL Team TWO at NAB Little Creek, Virginia, from May 1990 until he was killed in a parachute training accident in Coronado, California, on July 15, 1991. Ernest Greppin was buried at Hingham Cemetery in Hingham, Massachusetts.

The Sailor's Creed:

I am a United States Sailor.

I will support and defend the Constitution of the United States of America and I will obey the orders of those appointed over me.

I represent the fighting spirit of the Navy and those who have gone before me to defend freedom and democracy around the world.

I proudly serve my country's Navy combat team with Honor, Courage and Commitment.

I am committed to excellence and the fair treatment of all.