Stare Master

Fluttershy has great experience with all kinds of animals, but it is an entirely different story when she offers to take care of Apple Bloom, Scootaloo, and Sweetie Belle for the night. Will she be able to keep them out of trouble, and what exactly is "The Stare"?
My Little Pony; Friendship is Magic - Season 1, Song #8: "Hush Now, Quiet Now Lullaby