X: A Fabulous Child's Story is author Lois Gould's 1972 short story (which was later adapted into a picture book in 1978). It tells the story of the eponymous child called X, who is raised by their parents as part of an experiment which allows only for the parent and scientists to know the child's gender. Needless to say, the fact that X's gender is not known causes some confusion amongst teachers and students. However, the children in X's life ultimately overlook this fact and treat the child with respect and kindness (though most of the adults in X's life do not).
At release, X: A Fabulous Child's Story received mostly positive reviews. However, many reviewers questioned whether or not Gould successfully challenges the role of gender and sexuality in society. Others have suggested that the book is ironic because it spends a lot of time arguing against gender roles and gender binary and then ends up putting X's sibling into a binary system. Many, however, liked the book. Publisher's Weekly wrote that X: A Fabulous Child's Story is "witty, innovative, and sophisticated" and "likely to stimulate discussion."