Son of the late Daniel M. and Gertrude (Powers) Sheahan, David Reeves Sheahan was born on September 19, 1933, in Fall River. He was a graduate of Coyle High School, Class of 1951.
Colonel Sheahan had a Bachelors Degree in English Literature from Holy Cross College and a Masters Degree in Political Science from Auburn University earned in June 1955 and July of 1971 respectively. He was also a graduate of the Air Command Staff College and had completed the Air War College course.
Colonel Sheahan received his commission as a second lieutenant through the Reserve Officer Training Corps (ROTC) program at Holy Cross College in June, 1955. He had a wide variety of leadership roles in communication and deployment readiness throughout his career.