As the inhabitants of a peaceful home aquarium turn in for the night, Fish and Crab climb into their beds. Ready for some shut-eye, Crab clicks off the lamp, casting the room's cheerful colors into grays, and falls right to sleep. Fish, on the other hand, still has their eyes wide open, anxious thoughts racing through their mind. "Crab?' Fish ventures, Are you sleeping?'" They keep asking until Crab finally gets up to let Fish vent their worries. A hilarious flood of what-ifs touching on alien abduction, raining frogs, black holes, and more ensues before Fish finally falls asleep. Unfortunately, a few of Fish's concerns get under Crab's shell, this time leaving the crustacean wide-eyed as the lights go out. Coppo's comedic take on runaway worries will put anxious children at ease with its simple yet expressive artwork, absurdity, and relatability. Those who connect with Elephant and Piggie books will find this a similar reading experience whose lessons on friendship, listening, and managing emotions go down swimmingly.

Fish's fretting keeps roommate Crab up at night.Crab and Fish live together in their cozy aquarium home. Crab is happy to sleep, turning off the light (resulting in a desaturated overlay) only for Fish, unable to sleep because of worries, to pipe up. Fish's concerns range from the relatable (strange noises, unexpected animals, and contagious illness) to the outlandish (alien abduction, oversleeping into the future, and winding up in a parallel universe); the book even takes a dip into metafiction with the characters staring at readers as Fish asks, "WHAT IF WE ARE CHARACTERS IN A BOOK?" Finally, having voiced their anxieties, Fish relaxes and falls asleep, though these worries now keep Crab awake. This tale is told through minimalistic text, primarily dialogue. Things said by anyone other than the titular characters (including the narrator) are in italics, things said by Fish are in a regular font, and words spoken by Crab are in bold. While the story, especially the twist at the end, isn't terribly unexpected, the predictability that will inhibit rereadability for some will reassure others. The art is lineless, with colorful (excepting the lights-off pages) shapes, as simple as the clean, sans-serif font, resulting in a cohesive feel (though some stark-white backgrounds undermine the nighttime premise). (This book was reviewed digitally.) Silly what-if questions arranged into a light but visually appealing bedtime story. (Picture book. 4-7)