Objective: The purpose of this study was to determine the quality and effectiveness of a structured, competency milestone-based pediatric sonographer onboarding program and continuing educational curriculum and to ascertain if these experiences influence their professional development, job satisfaction, and retention. Materials and Methods: A survey was distributed to the sonographers in a single echocardiography laboratory. The anonymized data were collected and analyzed to generate descriptive statistics. Results: There were 36 sonographers who responded (80%) and 15 (42%) training with the new onboarding curriculum. The majority reported a positive feeling of preparedness for independent practices (80%) with hands-on teaching, timely feedback, and case-based learning rated as the most effective teaching methods. Physician feedback was preferred over sonographer trainer feedback. Most sonographers perceived the advancement of their knowledge as important for professional growth, job satisfaction, and retention. Conclusion: A structured onboarding program for new hires based on competency milestones was effective in preparing pediatric cardiac sonographers for independent practice. Hands-on bedside training, timely constructive feedback, and case-based learning should be included in the curriculum to ensure high-quality teaching. Physician engagement is highly valued and should be incorporated into the workflow. This study may suggest that continuing education helps positively influence the sonographer’s attitudes toward professional development, job satisfaction, and retention.