
A parent should reach for this book when their older child is struggling with the intense, often messy feelings of jealousy toward a new baby. The story follows Lilly, a young mouse who is dethroned as the center of attention by her new brother, Julius. She thinks he's disgusting and disruptive, and she isn't shy about saying so. This book brilliantly validates an older sibling's negative feelings through humor, making them feel seen and understood. It shows that these big, uncomfortable emotions are normal and that they can coexist with a fierce, protective love that emerges when it's needed most. It’s perfect for opening up a conversation about sibling rivalry.
Sibling jealousy is the main topic. The book is direct and uses hyperbolic, almost mean language from Lilly's perspective (“If he was a number, he would be zero”). This is handled with humor and is ultimately resolved with a positive, loving outcome. The approach is secular and realistic. The resolution is hopeful and developmentally appropriate.
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Sign in to write a reviewA 3 to 6-year-old who has recently become an older sibling and is exhibiting classic signs of jealousy: acting out, making negative comments about the baby, or regressing in behavior. They need their big, uncomfortable feelings validated in a safe, humorous way.
The book can be read cold. However, parents should be prepared for Lilly's very direct, negative comments about Julius. It's helpful to be ready to pause and say, "Wow, Lilly is feeling really angry. Have you ever felt that way?" instead of immediately scolding the character's behavior. The scene where Lilly imagines Julius disappearing in a puff of smoke could be one to note, but it's presented comically. The parent has just heard their older child say something like, "I hate the baby," or "Take him back to the hospital." They might have witnessed the older child trying to scare or pinch the baby.
A 3-year-old will likely connect with the raw emotion and the physical comedy of the illustrations. They'll grasp the basic "Lilly is mad, then Lilly is happy" arc. A 6 or 7-year-old can appreciate the more nuanced humor, the cleverness of Lilly's insults, and the psychological truth of the ending: it's okay for me to criticize my family, but not for an outsider to do it.
Unlike many new sibling books that focus on the older child being a "helper," this book lives almost entirely in the negative space of jealousy. Its genius is in its unflinching validation of those feelings through humor. The resolution isn't about Lilly learning to be "nice," it's about her innate, protective sibling bond being activated by an external threat. This is a much more cathartic and realistic emotional journey for many children.
Lilly, who was once the center of her parents' world, despises her new baby brother, Julius. She insults him (“the baby of the world? Disgusting.”), tries to scare him, and expresses her jealousy in many ways. Her parents gently try to correct her. The turning point comes when a visiting cousin, Cousin Garland, criticizes Julius. Lilly fiercely defends her brother, finally claiming him as her own and showing her deep, protective love.
This overview was generated by AI based on the book's content and reviews, and may not capture every nuance.