BackgroundParents of children with a rare progressive life-limiting illness are at risk for parental posttraumatic stress disorder (PTSD). Studies on the treatment of parental PTSD with eye movement and desensitization reprocessing (EMDR) therapy in pediatric practice are lacking. Therefore this study aims to evaluate the feasibility and effectiveness of time-limited EMDR therapy in reducing PTSD symptoms, comorbid psychological symptoms, distress, and parental stress.MethodsMono-center randomized clinical trial conducted between February 2020 and April 2021. Fourteen parents (N = 7 mothers, N = 7 fathers) of mucopolysaccharidosis type III patients reporting PTSD symptoms on a (sub)clinical level were assigned to EMDR or a wait-list control condition followed by EMDR. Four sessions of EMDR (each 90 min) divided over two half-days were offered. Measurements were conducted at baseline, post-treatment/post-waitlist, and 3-months post-treatment. The primary outcome was PTSD symptom severity (PTSD Check List for DSM-5). Secondary outcomes included comorbid psychological symptoms (Brief Symptom Inventory), distress (Distress Thermometer for Parents) and parenting stress (Parenting Stress Questionnaire). Between-group comparisons pre-to-post treatment (N = 7 EMDR vs. N = 7 wait-list) and within-group comparisons (EMDR, N = 14) from pre-to-post treatment and from pre-treatment to 3-months follow-up were carried out per intent-to-treat linear mixed model analyses.ResultsCompared to wait-list, EMDR resulted in a significant reduction on total PTSD symptom severity (d = 1.78) and on comorbid psychological symptoms, distress and parenting stress (d = .63–1.83). Within-group comparisons showed a significant effect on all outcomes at post-treatment (d = 1.04–2.21) and at 3-months follow-up (d = .96–2.30) compared to baseline. EMDR was well-tolerated, associated with a low drop-out rate, a high therapy adherence and no adverse events.ConclusionTime-limited EMDR reduces PTSD symptoms, psychological comorbidity, distress and parenting stress in parents of children with a rare progressive life-limiting illness. This treatment was feasible for these overburdened parents. Recurrent monitoring of PTSD symptoms, and, if needed, offering this time-limited type of trauma treatment should be introduced in everyday pediatric practice.Trial registration Netherlands Trial Register, NL8496. Registered 01-04-2020, https://trialsearch.who.int/Trial2.aspx?TrialID=NL8496.