Background The quality of parent–child attachment is one of the essential factors related to the possible outcomes in the aftermath of child sexual abuse (CSA). The types of attachment insecurity are well-known, as are its mediating effects on CSA and the other way around. However, one of the main issues relating to what we know about the long-term development of those attachment patterns is the aftermath of CSA in very young children. Our study is part of the larger, ongoing Amsterdam Sexual Abuse Case (ASAC) study. It provides new insights into the existing scientific literature because it concerns an exceptional study population consisting of extrafamilial sexual abuse, juridical proof of the sexual abuse, the extremely young age at the time of onset, and it provides insight into attachment patterns over a period of more than 10 years after CSA.Methods We have aimed to look into the parent–child attachment relationship in a unique group of children who have been sexually abused at a very young age (0–3 years old) using parent-report questionnaires over a period of a decade: from the start of the study 3 years after the disclosure of CSA until 13 years after CSA.Results These longitudinal results show fluctuations in reported attachment insecurity levels over the years. From 10 years after CSA and thereafter, we found levels of attachment insecurity to have decreased. Nevertheless, all children between 10 years after CSA and 13 years after CSA showed clinical levels of attachment insecurity.Conclusions To conclude, insecure attachment patterns in the aftermath of CSA appear to apply to children who were sexually abused during infancy or early childhood, even if the perpetrator is not a primary caregiver. Additionally, the results indicate the importance of long-term monitoring for children as well as their parents not only in the treatment of symptoms but also in terms of family support and parent–child attachment. Further longitudinal and multi-informant studies are needed to elucidate these results.
