Savvy concerns the Beaumont family, who develop supernatural powers on their thirteenth birthdays. As the novel starts, Mibs Beaumont is turning thirteen, and she doesn't know what her power will be. In her family, the power is important to the identity of the children and adults. While waiting for the school bus, Mibs's older brother Fish causes a storm, which is his power, and Will Junior, who is Mibs's friend, wonders what happened. He gives Mibs a birthday present: two fancy pens. She draws a smiling sun on Will's hand, and to her shock, it becomes animated and speaks. Mibs is scared and hides; Will tries to comfort her, but Fish misunderstands his intentions:
Fish, seeing me upset and not bothering to find out what might have happened, close in on Will Junior and spun him around, clocking him hard and fast in the eye with his fist. Will took the blow, stumbling backward along the aisle of the bus, and Bobby joined the scuffle....
(Law, Savvy, Google Books)
Later, Will Junior has a prominent black eye, which Mibs tends to, allowing them to grow closer. This is an example of character-created conflict, with the misunderstanding creating tension between the characters until things are sorted out. By showing the deep protective connection that Fish has with Mibs, his rivalry with Will Junior causes development for their characters, and also allows insight into the sometimes-silly teenage arguments; in this case, of course, the addition of supernatural powers makes the stakes somewhat higher than adolescent emotion.