“folie à deux”

Ellis (2000: 218) identifies a similarity between folie à deux and PAS. She states:

... the core feature of folie à deux is that a delusion develops in one person who is involved in a close relationship with another person who already has a delusional disorder. The primary individual is dominant in the relationship and gradually imposes his or her delusional system on the more passive and initially healthy second person. These individuals are usually related by blood ties or by marriage and have lived together for a long time, often in isolation. The most common dyads are husband to wife, sister to sister, and parent to children.