(written from a Production point of view)
He was married to fellow TOS guest actress Madlyn Rhue (Marla McGivers in "Space Seed") from 1962 through 1970 and had one child. Young and Rhue co-starred with each other (and George Murdock) in the 1964 Western He Rides Tall and, after their divorce, would co-star in the 1974 made-for-television movie The Sex Symbol (with Nehemiah Persoff).
Outside of Star Trek, he also made guest appearances on such television series as The Virginian, Mannix, and Mission: Impossible, as well as Fantasy Island, in which he appeared with his wife's "Space Seed" co-star, Ricardo Montalban. He also appeared in the 1975 TV movie The Lives of Jenny Dolan, with James Darren, Percy Rodriguez, and Paul Carr.
Among his feature film credits are: the 1964 western Taggart, in which he played the title role; the 1969 musical western Charro!, co-starring Elvis Presley, Garry Walberg, and James B. Sikking; the 1972 blaxploitation classic Black Gunn, with William Campbell and Bernie Casey; the 1973 thriller The Outfit with Joanna Cassidy, Elisha Cook, Jr., and Roy Jenson; and the 1974 drama Rape Squad, with Stanley Adams.
Young retired from acting following a guest appearance on the hit science fiction series Quantum Leap, which starred future Star Trek: Enterprise actors Scott Bakula and Dean Stockwell. He died of lung cancer in Hollywood, California, on the same day as Star Trek: Deep Space Nine guest actor Lawrence Tierney.