Technical Sergeant Gaaei was a veteran of World War II. In Korea, he was a member of Company G, 3rd Battalion, 1st Marines, 1st Marine Division. On 2 March 1951 at Hill 303 near Hoengsong, Korea, while instructing his runner to take a message to another headquarters, he was killed by artillery fire.

Gaaei was awarded the Purple Heart, the Combat Action Ribbon, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.