Background: Traumatic injury is a leading cause of death and disability in children and young adults. There is a lack of evidence-based literature and guidelines on supporting families after severe child injury. This study aimed to assess the family needs and factors associated with those needs. Methods: A prospective multicenter follow-up study conducted at two Norwegian trauma centers involving children (aged 0–18 years) who sustained a moderate or severe traumatic injury with a New Injury Severity Score > 9. Sociodemographic and injury variables were recorded at baseline. The Family Needs Questionnaire—Paediatric Version, ranging from one (not at all met) to five (completely met) was completed by parents to assess the family needs at the 6-month follow-up. Bivariate logistic regression analyses were conducted to identify the factors associated with the family needs at 6 months post-injury. Results: Of the 63 children included, 38 (68% boys) with a mean age of 9.9 years (SD = 5.8) were available for follow-up. At 6 months, 82% reported needs for health information with a mean score of 3.8 (SD = 1.0), and involvement with care with a mean of 3.7 (SD = 1.2). Additionally, 71% reported emotional support needs (mean score 2.6, SD = 1.3). A higher number of injuries and a lower age of the child were significantly associated with increased odds of having more family needs. Conclusions: After moderate to severe pediatric traumatic injury, families report a need for health information, involvement in care, and emotional support. Paying attention to the number of injuries and the child’s age could help to identify families in need of information and support.