My Little Pony - Terror in the barn

One night, while Rainbow Dash was helping Applejack and Big Macintosh on the farm, she accidentally locked herself and Applejack in the barn.
While waiting for Big Macintosh to return and unlock the door, they decided to tell each other scary stories to pass the time. Since Rainbow Dash didn't have any good stories, Applejack decided to tell her an anecdote about something her brother Big Macintosh and his friend Terry had experienced when they were children.