In this middle-grade Bridesmaids, hilarity ensues as triplets have to stop a wedding! One bride. Two boys. Three flower girls who won't forever hold their peace. What could go wrong with this wedding? Everything! The Brewster triplets, Dawn, Darby, and Delaney, would usually spend their summer eating ice cream, playing with their dog, and reading about the US Presidents. But this year they're stuck planning their big sister Lily's wedding. Lily used to date Alex, who was fun and nice and played trivia games with the triplets, and no one's quite sure why they broke up. Burton, Lily's groom-to-be, is not nice or fun, and he looks like an armadillo. The triplets can't stand to see Lily marry someone who's completely wrong for her, so it's up to them to stop the wedding before anyone says 'I do!' The flower girls will stop at nothing to delay Lily's big day, but will sprinklers, a photo slideshow, a muddy dog, and some unexpected allies be enough to prevent their big sister - and the whole Brewster family - from living unhappily ever after?