When a child has a psychotic disorder (schizophrenia or another type of psychosis), they usually experience a series of difficulties in their relationships with others and with their performance (academic, sports), and a level of emotional suffering that can be high. Furthermore, if they are an adolescent, their life expectations (and those of their parents) may change due to this discomfort and these difficulties. All of this means that in some cases depressive symptoms develop after a psychotic episode , which are a normal reaction to the process experienced. In this case, it is usually referred to as post-psychotic depression.

On the other hand, it can also happen that depressive symptoms appear from the beginning of the psychotic disorder and are part of the same process. It is possible that the two syndromes occur at the same time, and then we would be talking about psychotic disorder with depressive symptoms, or depression with psychotic symptoms, or schizoaffective disorder, depending on the specific aspects of this "coexistence" of depressive and psychotic symptoms.