This study aimed to evaluate the effectiveness of a digital education and simulation-supported training intervention on mothers' knowledge and practices regarding colostomy care for their children. A randomized controlled trial was conducted among 120 mothers of children with colostomy recruited from the pediatric general surgical unit and outpatient clinic at Monufia University. Participants were randomly assigned to either a study group (n = 60) or a control group (n = 60). The intervention consisted of a multi-component educational program including a digital booklet delivered via WhatsApp, voice-over explanations, animated videos, interactive simulations, researcher demonstration using a simulation model, supervised hands-on practice, daily postoperative supervision, and WhatsApp follow-up support. The control group received routine hospital care. Data were collected using a structured knowledge questionnaire and an observational practice checklist at baseline, immediately post-intervention, before discharge, and at 12-week follow-up.