However, research into pediatric medical traumatic stress (PMTS), also known as posttraumatic stress symptoms from medical events, is lacking. The objectives of this cross-sectional study of children and adolescents with inflammatory bowel disease, chronic pancreatitis, and cystic fibrosis were to estimate the prevalence of medical potentially traumatic events (PTEs) and PMTS, investigate potential risk factors for PMTS, and investigate potential consequences of PMTS. This cross-sectional investigation assessed PTEs and PMTS using validated self-report methods. The study’s goals were reached using descriptive statistics and regression analyses. Over 2/3rd of the children (91 out of 132, 69%) said they had experienced a potentially upsetting medical episode. Around 48 (36%) reported experiencing PMTS symptoms. In multivariate analysis, PMTS was linked to parents’ PTSD, hospitalizations, and the number of medications their children needed. Absenteeism from school, parental opioid use, diminished quality of life, and missed work time were all mentioned as possible outcomes of PMTS. There was a high prevalence of medical PTEs and PMTS throughout the sample population. Potential links between PMTS and parental PTSD, functional deficits, and other health issues were discovered during this exploratory study. Research into the early diagnosis, prevention, and treatment of PMTS is crucial to improving the health and well-being of young children.