It can be hard to make friends when your personalities clash.McAvoy's friendship tale features two girls who recount how they learned to be friends and bonded over their personality differences. Cookie is a brown girl who loves science, and Milk is a white girl who loves sports. The girls banter back and forth, recalling how they discovered they have fun playing together—especially when they use their complementary personalities to accomplish something awesome! If Milk wants to skate, then Cookie is in the background helping her reach her fullest potential by building a ramp, for instance. Throughout the book, early readers will love guessing what Milk's younger brother is trying to communicate (he also slyly breaks the fourth wall) when he introduces fans to exciting new science words such as "engine's ear!"—er, "engineer." Caregivers will also find helpful starter questions to ask when exploring differences with their kids. Those questions provide a framework within which young readers may learn to value and accept differences in themselves and others. Even after the story, readers are provided with a list of powerhouse women who were either "smart" or "sporty," and a glossary of words encourages supportive friendships. Gibson's simple, cartoon illustrations playfully remind girls that there are universal commonalities in sisterhood.Smart, sassy, supportive girl power to the max! (Picture book. 3-6)