Psychological Medicine; Cambridge Vol. 48, Iss. 14,  (Oct 2018): 2321-2328. Being bullied by a sibling has been recently identified as a potential risk factor for developing depression and self-harm. It is unknown whether this risk extends to other serious mental health problems such as psychosis. We investigated whether sibling bullying victimization or perpetration in middle childhood was prospectively associated with psychotic disorder in early adulthood.. To read the full article, log in using your MPFT NHS OpenAthens details.