Psychosexual development character Oedipus, who unwittingly killed his father, Laius, and sexually possessed his mother, Jocasta. Analogously, in the phallic stage, a girl's decisive psychosexual experience is the Electra complex, her daughter–mother competition for psychosexual possession of father. This psychological complex derives from the 5th-century BC Greek mythologic character Electra, who plotted matricidal revenge with Orestes, her brother, against Clytemnestra, their mother, and Aegisthus, their stepfather, for their murder of Agamemnon, their father, (cf. "Electra", by Sophocles). Initially, Freud equally applied the Oedipus complex to the psychosexual development of boys and girls, but later developed the female aspects of the theory as
Penis envy by removing the man from the penis or the penis from the man). Freud's theories regarding psychosexual development, and in particular the "phallic stage", were early challenged by other psychoanalysts, such as Karen Horney, Otto Fenichel and Ernest Jones, though Freud did not accept their view of penis envy as a secondary, rather than a primary, female reaction. Later psychologists, such as Erik Erikson and Jean Piaget, challenged the Freudian model of child psychological development as a whole. Jacques Lacan, however, took up and developed Freud's theory of the importance of what he called ""penisneid" in the unconscious of women"