Holahan married Loretta Swit after guest-starring on her show M*A*S*H. Interestingly enough, his last name "Holahan" is similar to Swit's last name on the show, "Houlihan.".
Graduated from Andover in 1961 and Yale in 1965. He then served in the Navy.
Honeymooned with his 2nd wife, Loretta Swit in Egypt.