Tony Gordon was the son of James Gordon. Originally referred to as a college student, Tony later disappeared while hiding from Communist spies. He was later reunited with his sister Barbara (a.k.a. Batgirl) and perished in a battle with the Sino-Supermen.
[There has been no mention of Tony in current DCU continuity, which suggests that he does not exist post-Crisis. It's also possible that his place has been taken by Gordon's other son, James Gordon Jr., or that the two of them are even one and the same.]