He took advantage of a veteran's program in Oklahoma and accomplished his goal.
Sadler felt the call to serve his country when he was just 16-years old.
He dropped out of high school and lied about his age so he could join the military and fight in World War II.
Sadler now aims to enroll in college.
The veteran's program allows anyone who left high school prior to graduation to serve in World War II, the Korean War or the Vietnam War to get their diploma.