How does the superego evolve from the Oedipus complex?

It is through the development of emotions and reasoning that the superego evolves from the Oedipus complex.

Specifically, the Oedipus complex is a stage through which boys pass between the ages of three and six (3-6). During this stage, they become close to the mother figure as their main informational source and distant from the father figure, who becomes the role model later on in the normal development of a male identity. They pass on to the next, latent stage by becoming fearful of castration by the opposite-sex parent and by reasoning that the role model for subsequent personal happiness and professional development actually is the same-sex parent.