Sunset comes home to Equestria for the holidays, but her family reunion is short-lived when her mother falls ill. She and Spitfire will have to journey across Equestria to find a cure and make a Hearth's Warming miracle.
One drunken night of science and magic has led Sunset and Twilight to create an artifical human named Dawn that recognizes both girls as her mothers. But the magic powering her can only last so long.