Risk factors for sibling bullying in families with an autistic child

Autistic children experience sibling bullying at an increased rate compared to the general population. Despite the negative outcomes associated with being both a victim and a perpetrator of sibling bullying in childhood, there is a paucity of research investigating why this form of bullying occurs in families with an autistic child. This thesis aimed to examine and identify risk factors associated with sibling bullying in these families. In the first study, secondary data from the Millennium Cohort Study was used to assess the relationships between parent- and child-level factors and sibling bullying involvement of autistic children. The second study employed an online survey, completed by parents of autistic children, and aimed to model the relationships between sibling bullying and child-level factors. Both studies identified factors at the child-, parent-, and family-level that are significantly associated with sibling bullying; in line with prior research, it was identified that use of harsh parenting tactics, the gender of the victim, child challenging behaviour and specific special educational needs or disabilities (SENDs) were related to the likelihood of sibling bullying. On the contrary, factors such as parental mental health, gender of the perpetrator, and household income were shown to not be associated with sibling bullying rates. The nature of the relationships between these factors and sibling bullying are discussed, and theories are suggested as to the nature of their interactions. Finally, a summary of the research described is discussed, and implications for future research and interventions in sibling bullying are considered.