O Estigma (1935)

Safely from behind some shrubbery, Johnny Hume, a boy of 6 or 7, witnesses the slaughter of his mother, father and brother by the guns of a gang led by "the Cat". Twenty years later finds Johnny grown to manhood, an expert bronc rider and target shooter - but paralyzed with fearful memories in an actual gunfight. This is brought home to him when some outlaws stick up the local saloon and Johnny ends up cowering behind the bar.