Mirror, Mirror On The Wall, The Object Who Is Bravest Of Them All

I bet that you have heard of the mirror. The mirror who saved the girl from the face of death. The mirror that sacrificed itself for another and the same mirror who saved the life of the girl and an incalculable more in the future. Well if you haven't, then here lies the story of the gallant reflector.
(btw this is a short story)