To examine the association between child maltreatment (abuse and neglect) in one sibling and that in another as well as associated risk factors.
The participants were 520 sibling pairs enrolled in a population-based birth cohort study in Brisbane, Australia (N = 1040). Exposure to suspected child maltreatment was measured by linkage with state child protection agency data. Self-reports of childhood sexual abuse were also collected at the 21-year follow-up.
There were notifications in both children for 8.5% of the sibling pairs (n = 44). A notification in the first sibling was associated with a 60-fold increase in the likelihood of a notification in the second sibling (95% confidence interval: 29.3–125.1), resulting in nearly three-quarters being the subject of a report. In terms of the subtypes, neglect revealed the strongest association, followed by sexual abuse. At the 21-year follow-up, 58% of second siblings reported sexual abuse when the first sibling disclosed similar experiences. On adjusted analyses, maternal age of <20 years was the strongest and most consistent predictor of abuse, with indigenous status, maternal depression, parental relationship, and familial poverty playing a lesser role.
Our results highlight the close association between child abuse in one sibling and maltreatment in a second sibling as well as possible risk factors. Greater awareness of these factors may inform interventions, particularly primary and secondary prevention.