Milo grapples with jealousy when a newcomer arrives. Milo and his best friend, Jay, live next door to each other and are inseparable. But when Suzi moves in across the street, everything changes. Jay and Suzi are always laughing (loudly) together or playing, and Milo feels left out. The "squirmy feeling" inside him suddenly grows into a monster. Not only "a green-eyed monster," but a bright green spiky splotch that radiates frustration with vectors and stars shooting out. The monster sticks with Milo, validating his anxieties ("IT'S NOT FAIR!" "Jay is YOUR friend, not Suzi's!") and encouraging irrational thoughts ("the monster hissed that they were having more fun without him"). Milo's eyebrows furrow, and his hands clench; he's the picture of anger and dejection. All of the color drains from his surroundings, the green of the monster popping against the gray setting. Luckily, Suzi breaks the monster's hold by asking questions, highlighting the importance of communication. Percival's over-the-top visuals will resonate with young readers, many of whom have likely been in Milo's shoes and will appreciate seeing someone else conquer their green-eyed monster. Coping methods for when friendships feel a bit "wobbly" are appended in a letter from the author. Milo has slightly tanned skin, while Jay is brown-skinned, and Suzi is pale-skinned with bright red hair. (This book was reviewed digitally.) Sure to help young readers recognize--and reconcile with--their own green-eyed monsters. (Picture book. 4-7) Copyright (c) Kirkus Reviews, used with permission.