During the phallic stage, the primary focus of the libido is on the genitals. Children also discover the differences between males and females. Freud also believed that boys begin to view their fathers as a rival for the mother’s affections. The Oedipus complex describes these feelings of wanting to possess the mother and the desire to replace the father. However, the child also fears that he will be punished by the father for these feelings, a fear Freud termed castration anxiety.