RESUMO
BACKGROUND: Folie à deux is a very rare psychiatric syndrome in which a psychotic symptom is transmitted from one individual to another. We present a case of folie à deux occurring during childhood, which is not an usual presentation of this syndrome. In this case, the disorder is correlated with child abuse and neglect, which possibly had a role in the development of the symptoms in our case. CASE PRESENTATION: We present a case of folie à deux between an "induced" 9-year-old black Brazilian boy and the "inducer", his grandmother. They were found to be sharing similar auditory and visual hallucinations and delusional beliefs. The boy was neglected by his parents and was being cared for by his grandmother, who had a history of mental disorder. CONCLUSIONS: The close relationship between the boy and his grandmother, the family history of first-degree psychosis, and the child abuse and neglect suffered by the boy may have altered his vulnerability to early-onset psychosis and, in this case, folie à deux.
