The film focuses on Kay's relationships with her boyfriend Louis, her parents and her emotionally unhealthy sister, Sweetie. Kay is quiet and superstitious, loving Louis because of the words of a fortune teller and experiencing deep foreboding towards a tree he attempted to plant in their yard. Sweetie, from Kay's perspective, is selfish in her severe mental illness. Kay's father chooses to ignore most of the erratic, childish behavior (though she has been hospitalized before) because he loves her as a little girl. Throughout, there are flashbacks of Sweetie dancing, singing and performing small, circus-like tricks with his assistance; he wants the family to remain close and dislikes when Kay acts enraged with Sweetie. The mother admits he indulges her. Louis, however, has found some freedom from his increasingly disconnected relationship with Kay because Sweetie lives uninhibited, with vigor and emotion (though extreme).