How does Ian serve as an important mentor to his sister, Becca, in the novel, After the Kiss?

Ian, Becca's older brother, helps her see that Alec was not everything that Becca thought he was. Ian also helps Becca see that high school is not as important as it seems, but rather, a stepping stone to the real world. Ian is a good brother who helps Becca see the growth that has taken place in her life in the course of the novel.