Coming to Princeton from Nashville, Tenn., he brought a lifelong love of music with him and played violin and viola in the orchestra for four years. He majored in mathematics. After graduation he went into teaching. He then earned a Ph.D. in 1971 from the University of Wisconsin. Todd then established a tax-accounting practice, which he continued until his retirement in 2008.
Todd married Barbara Lee Clements in 1969, and they settled in her hometown of Houston. He continued his love of music by performing in the first-violin section of the Houston Civic Symphony for 29 years, playing with amateur string quartets, and enjoying performances of the Houston Grand Opera. He was also an early adopter of the Apple II computer for both work and play.
He and Barbara Lee did not have children, but were devoted to their pair of Maltese dogs. She predeceased him in 2013.