Biografia

He became the youngest drill instructor in the Marine Corps, and during his four years of service received a coveted Fleet appointment to the Naval Academy, which he declined. In 1972 he was awarded one of the nation's highest honors, the Freedom Through Knowledge Award, sponsored by the National Space Club in association with NASA. In 1974 he was awarded the George Washington Honor Medal, the highest award of the Freedom Foundation at Valley Forge, as well as the Globe and Anchor Award from the Marine Corps. In 1976 the Veterans of Foreign Wars honored him with an award.

In 1943, as a recruit in Marine Corps boot camp at Camp Pendleton, CA, he participated in a boxing match. The referee was John Wayne, who was shooting a film there. In 1976 O'Brien played the last character killed on-screen by Wayne in Il pistolero (1976) (Wayne's last film).

Broke into acting by happenstance. While seeing an actress in Los Angeles, he visited her at a few of her rehearsals for a play. The director asked him to step in after the leading man dropped out of the show. A Los Angeles Times reporter saw the production and gave him an excellent review.

He and teacher Virginia Barber dated for 18 years before their marriage on 6/25/2006, at Forest Lawn Memorial Park in Glendale, CA. This was his first and only marriage; her second. She was 54; he was 81. The Rev. Robert H. Schuller, pastor of the Crystal Cathedral in Garden Grove, CA, officiated, and the couple was serenaded by friend Debbie Reynolds. Dubbed "A Wedding to Die For", the ceremony concluded with a cocktail reception.

Attended the (now closed) Kemper Military School in Boonville, MO.