We investigated the links between peritraumatic distress in children and in their parents following a potentially traumatic event, focusing specifically on the role that parents and family functioning can play in the development and maintenance of post-traumatic disorders in children. To this end, we examined a population of 41 children (aged 8 and above), and their parents, who had been admitted to the emergency room of a pediatric hospital due to an accident. The design included a two-step assessment: immediate reactions (in the hours following the event) and delayed reactions (5–8 weeks after the event). We used six questionnaires to assess reactions. The results indicated a statistically significant positive correlation between the intensity of the peri-traumatic distress of the parents and the level of post-traumatic symptoms observed later (5 to 8 weeks after the event) in the questionnaires administered to the children. Regarding educational practices, differences appear to be linked to maternal education practice and to the severity of child's symptomatology. Finally, a link has been established between changes within the family dynamic after a potentially traumatic event and the severity of child's posttraumatic symptoms. This study showed the extent to which the parents’ initial reactions can be decisive in the outcome for a child who has experienced a potentially traumatic event. The study highlights the importance of assessing parental responses as well as paying attention to the children when they arrive in a pediatric emergency room. The results are relevant for prevention and treatment of PTSD in children, as the integration of this parental dimension early on in the process may lead to improved identification of which young patients are at risk of developing post-traumatic symptomatology.