Investigating the impact of peer and sibling bullying: A prospective longitudinal study of associations with mental health in adulthood

Background: Peer bullying has been widely associated with poorer mental health outcomes. Sibling bullying has also been associated with poor mental health outcomes and peer bullying, however, is often normalised and overlooked as a rite of passage. The transition to school during preadolescents (age 9 to 12) has been identified as an important period of change both in peer and familial relationships and changes in bullying roles and behaviours during this time can shape a young person’s future mental health and wellbeing. Aims: To explore relationships between peer and sibling bullying across school transition age and understand how exposure to each at transition age associates with mental health and wellbeing outcomes at 17. Method: A sample of 724 youths were recruited as part of the data collection for Understanding Society, the UK Household Longitudinal Study (UKHLS) and followed up at age 10, 12 and 17. Regression models explored associations between peer and sibling bullying experiences between age 10 and 12, and outcomes at age 17. Interaction terms between the two forms of bullying were explored. Results: Significant associations were found between peer and sibling bullying involvement before and after the school transition. Low and moderate exposure to sibling bullying was associated with lower psychological distress and higher negative self-view. Consistently high exposure to sibling bullying was associated with lower satisfaction with life but higher positive self-view. Peer bullying was only associated positive self-view after adjusting for covariates. Interaction effects between bullying forms and positive self-view are discussed. Participant sex had the most significant association with psychological distress, negative self-view and satisfaction with life. Conclusion: The results highlight the importance of addressing sibling bullying during school transition age, and greater need for understanding the positive impact of bullying experiences, which appears under researched. Limitations and direction for future research are discussed.