He had a long career in art education and has many sculptures on public display, but he may be best known for That Which Might Have Been—his memorial to the four girls killed in the 1963 bombing of the 16th Street Baptist Church in Birmingham, Alabama.

Waddell was born in Des Moines, Iowa in 1921 and moved to Evanston, Illinois, at the age of ten.

[1] At the time, he was working at Buick Aviation Plant, Melrose Park, Illinois—as America had entered World War II.

[2] In 1949, they were married in a small ceremony with friends and fellow students, Leon Golub and Nancy Spero, as witnesses.

While in Chicago, Waddell designed a program for students with Down's Syndrome and varied mental and physical challenges at Bruno Bettelheim’s Orthogenic School.