Dynamics of family violence in mandatory and voluntary child protection support systems: A longitudinal within-family design

• Within-family changes in violence, stress, and child PTS were unrelated over time. • Change patterns within families are similar for mandatory and voluntary CPS. • Intra-familial processes are complex and require customized support. The current study aimed to examine the within-family longitudinal associations between family violence, parental stress, and child post-traumatic stress (PTS) symptoms in families involved in the Dutch child protection system. Specifically, differences in within-family longitudinal associations between families receiving mandatory and voluntary child protection services (CPS) were investigated using multi-group Random Intercept Cross Lagged Panel Models. A total of N = 1015 parents ( N = 331 mandatory CPS; N = 684 voluntary CPS) reported on the frequency of family violence, the level of parental stress, and child PTS symptoms at three timepoints over the course of 1.5 years using validated questionnaires. The results showed that within-family changes in family violence, parental stress, and child PTS symptoms were not related over time, except parental stress at the second wave predicted child PTS symptoms half a year later. However, this cross-paths disappeared when adding covariates to the model. On the between-family level, the associations between the random intercepts of family violence and parental stress, and parental stress and child PTS symptoms were significant, indicating that changes primarily occur on the between-family level and are mainly cross-sectional. No differences were found between families receiving mandatory and voluntary CPS. Intra-familial change might be more complex and might occur at a different pace than hypothesized in this study.