A self-schema is a belief or idea about oneself that leads to a bias that is self-perpetuating. It could consist of a particular role in society or a generalization based on social sterotypes. If a mother tells her daughter she looks like a tom boy, her daughter may react by choosing activities that she imagines a tom boy would do. Conversely, if the mother tells her she looks like a princess, her daughter might choose activities thought to be more feminine. The self-schema becomes self-perpetuating when the individual chooses activities based on expectations instead of desires.