Sylvia was a 19th century Human female living in Tombstone, Arizona at the time of the shootout at the OK Corral on October 26th, 1881. Sylvia was romantically involved with gunman Billy Claiborne and wanted to marry him.

In 2268, Sylvia was part of a bizarre recreation of the duel created by the Melkot to execute Captain James T. Kirk and his landing party. (TOS: "Spectre of the Gun")