Background. Sibling bullying is associated with mental health difficulties; both in the short and long term. It is commonly assumed that sibling bullying leads to mental health difficulties but observational studies rarely allow for such inferences to be made. Method. To ad-dress this gap in knowledge, we used a genetically sensitive design with data from the Avon Longitudinal Study of Parents and Children (maximum N=3,959). At ages 12-13 years, individuals self-reported their involvement in sibling bullying, as a victim and perpetrator, and parents reported on their child’s mental health difficulties. Polygenic scores, in-dices of genetic risk for psychiatric disorders (major depressive disorder and attention deficit hyperactivity disorder) were computed using children’s genetic data. Regression and structural equation models were fitted to the data. Results. Sibling bullying and polygenic scores both independently predicted mental health difficulties but the relationship between sibling bullying and mental health difficulties was not moderated by genetic risk. Addition-ally, polygenic scores for mental health difficulties were associated with both sibling bully-ing and mental health difficulties. Conclusion. These findings suggest that the relationship between sibling bullying and mental health difficulties is not simply causal; sibling bullying and mental health difficulties may be, at least partly, related due to shared genetic etiology.
|Publication status||Published - May 2023|