What do you do with a muy bad day? In this heartwarming dual-lingual picture book from debut author Melanie Wick Singer with illustrations by Natalia Jiménez Osorio, one girl learns from her grandmother how to turn a muy bad day into a fiesta! Martina just had the worst day, ever. She fell in a mud puddle, swallowed a bug, stepped on un grande wad of gum, and ruined her lucky calcetines forever! When she tells her grandmother all about her muy bad day, Abuela has a few ideas for how to handle all the big feelings. Will anything be enough to turn her muy bad day around? With humor, love, and a little bit of music, anyone can turn un día muy malo into a fiesta--because even the worst days are worth celebrating!