Don't freak out, you did, too. According to famous Psychologist Sigmund Freud, all children go through "Psychosexual Development".
Oedipus —
The boy focuses his libido (sexual desire) upon his mother, and focuses jealousy and emotional rivalry against his father — because it is he who sleeps with mother. To facilitate uniting him with his mother,
the boy's id (well known as the "devil" on your shoulder) wants to kill father (as did Oedipus), but the ego, pragmatically based upon the reality principle,
knows that the father is the stronger of the two males competing to possess the one female. Nevertheless,
the boy remains ambivalent about his father's place in the family, which is manifested as fear of castration by the physically greater father; the fear is an irrational, subconscious manifestation of the infantile Id.
Electra — Whereas boys develop castration anxiety,
girls develop penis envy that is rooted in anatomic fact: without a penis, she cannot sexually possess mother, as the infantile id demands. Resultantly,
the girl redirects her desire for sexual union upon father; thus, she progresses towards heterosexual femininity that culminates in bearing a child who replaces the absent penis. Moreover, after the phallic stage,
the girl's psychosexual development includes transferring her primary erogenous zone from the infantile ****oris to the adult vagina. Freud thus considered a girl's Oedipal conflict to be more emotionally intense than that of a boy, resulting, potentially, in a submissive woman of insecure personality.
Sexual infantilism — In pursuing and satisfying his or her libido (sexual drive),
the child might experience failure (parental and societal disapproval) and thus might associate anxiety with the given erogenous zone. To avoid anxiety, the child becomes fixated, preoccupied with the psychologic themes related to the erogenous zone in question, which persist into adulthood, and underlie the personality and psychopathology of the man or woman, as neurosis, hysteria, personality disorders, etc.
There are 5 stages; Oral, Anal, Phallic, Latency, and Genital.
The
Oral stage is between birth and 1 year old, where the erogenous zone is the mouth. The kinds of fixation that arises from the oral stage include;
Orally aggressive: chewing gum and the ends of pencils, etc.
Orally Passive: smoking, eating, kissing, oral sexual practices
Oral stage fixation might result in a passive, gullible, immature, manipulative personality.
The
Anal stage occurs between 1 - 3 years old, and the erogenous zone is excreting waste from the bladder and bowel. Kinds of fixation;
Anal retentive: Obsessively organized, or excessively neat
Anal expulsive: reckless, careless, defiant, disorganized, coprophiliac
The
Phallic stage is when children 3 -6 years old discover they have genitals. This when the Oedipus and Electra stuff comes in, and I have already covered that.
The
Latency stage is when everything settles. All sexual feelings become dormant around this time, from age 6 to puberty. However, if fixation occurs in this stage, sexual unfulfillment can occur.
The
Genital stage. From puberty until death. Pretty much all of your sexual feelings mature and fixation in this stage can result in frigidity, impotence, and unsatisfactory relationships.
So to sum it all up, Freud believes that every child develops sexual desires for the opposite gender parent. The child believes they will be rejected by parents/society and so the child focuses on other things to vent their anxious feelings onto. These "other things" are the things in the stages, which include the mouth, bladder, bowel, and genitals. The fixations on these parts of the body lead to insecurities and psychological problems in later life.
We are learning all of this at school and tbh, I think Sigmund Freud couldn't get any. In his insecure state, he made up a theory that every child developed feelings for their parents and that we found pleasure in our body parts (as children) just to make everyone feel awkward about themselves.