Book 11 in The New York Times bestselling Ivy & Bean series.Ivy and Bean are back, and they are funnier than ever. Ivy's worried. She's read a lot of books about only children, so she knows that they are sometimes spoiled rotten. They don't share their toys. They never do any work. They scream and cry when they don't get their way. Spoiler alert! Ivy doesn't have any brothers or sisters. That's why she's worried. How can she keep from getting spoiled? She could give away all her clothes, but she'd probably get in trouble. She could give away all her toys, but she likes her toys. There's really only one solution: she needs a baby sister, on the double! Luckily, Ivy and Bean know just where to get one.