The fourth season picks up right after graduation with the family and Emmett discovering Bay's impulsive decision - and no one is happy about it. Meanwhile, Daphne is determined to prove herself worthy of her switchster's sacrifice while also dealing with the challenges of a whole new world of college.
In the first season, the lives of Bay Kennish, who grew up in a wealthy family with two parents and a brother, and Daphne Vasques, who grew up with a single mother in a poor neighborhood, are turned turned upside down when they discover they were accidentally switched as newborns in the hospital. When financial difficulties arise, the Vasques move into the Kennishes' guest house, giving everyone a chance to get to know each another.