Traditionally, cinema relied on the "evil stepmother" trope—a legacy of fairy tales like Cinderella and Snow White
The film follows Pete and Ellie (Mark Wahlberg and Rose Byrne), a childless couple who decide to foster-to-adopt. They are immediately confronted with the "blended" reality: the biological mother is still in the picture, the oldest daughter (Lizzy) is fiercely resistant, and the younger son has behavioral trauma.