Baby X
Baby X is the central character in the story. X is born to the Joneses, who raise X without a gender. X is a happy child with a number of interests, but faces difficulty from other children and their parents when they go to school. Eventually, X is determined to be completely mentally and emotionally sound, despite arguments that they are "mixed up."
The Joneses
The Joneses are X's parents. They agree at the beginning of the story to raise X without ascribing them a specific gender, though they are aware of the baby's sex at birth. The Joneses support X and do everything they can to give X a healthy life free from the pressure of either a male or female upbringing.
Scientists
The scientists in the story are the ones responsible for X's genderless upbringing. They find the Joneses and create the lengthy Instruction Manual to help them raise X accordingly. The scientists are in charge of an experiment (referred to as "Xperiment" in the story) in which X will be raised without the consideration of sex.
Other Children
When X goes to school, the Other Children are confused by X's clothing, interests, and behavior. They cannot understand why X does not act like either a boy or a girl, or conversely, why X acts like both a boy and a girl. The Other Children eventually become inspired by X and start acting in a genderless fashion as well, which causes outrage among their parents.
Parents
The parents of the Other Children are antagonistic throughout the story. Once their children begin imitating X's genderless lifestyle, they demand that X be examined and suggest that something is wrong with X. Ultimately, the parents accept that X is a completely normal child and invite the Joneses to join their parental committee at school.
Psychiatrist
The psychiatrist appears at the end of the story after the parents of the Other Children demand that X should be examined by a professional. After a long and rigorous session of questioning, the psychiatrist determines that X is completely fine, and that it is the parents who should rethink their position. When the psychiatrist emerges from the examination, he is crying.
