Gilbert weighed 10 1/2 pounds at birth. In 1939, he graduated from Ohio Mechanics Institute, Cincinnati. He volunteered for one year of military service in November of 1940, but the Japanese invaded Pearl Harbor two days before he was scheduled to return home in 1941. During WW II, Gilbert served overseas for 3 1/2 years. He was sent to Casablanca and joined the effort through Southern Europe. He helped build the bridge that enabled Gen. Patton to enter Berlin.

In 1947, Gilbert married Dorothy Yates (better known as Helen) and converted to the Mormon faith. They lived with their daughter Sandy in Denver, where Gilbert worked more than thirty years for the city as a bus driver. They later lived in Golden, Colo.