Major Glory - S13-E8
Other mistake: Matt rides into the Cavalry encampment looking for Festus, unchallenged by any sentry, unlike when Festus rode in.
Gunsmoke (1955)
1 other mistake in season 13 - chronological order
Starring: James Arness, Ken Curtis, Amanda Blake, Milburn Stone
Continuity mistake: Marshall Dillon buries an outlaw at Sarah's place. He installs a wood cross at the grave. Sarah comes out and they talk. When she leaves, the scene cuts back to Dillon and the cross is missing.
Dr. Galen 'Doc' Adams: I'll tell you why the Hagens live so long.
Festus Haggen: Why?
Dr. Galen 'Doc' Adams: 'Cause they're too dumb to know they're dead.
Trivia: Although they played father and son in this episode, Jack Elam was only six years older than Harry Dean Stanton.