This study addresses the issue that congenital heart defect (CHD) treatment in infants and young children causes limitations that reduce active play opportunities, delaying motor skill development, and preventing active lifestyle habits from being established in early childhood. Recent research has shown that the most sedentary children assessed in infancy continue to be the most sedentary children at school age. This suggests that an effective intervention to enhance active play and prevent sedentary lifestyles must target children with CHD in infancy.

The investigators hypothesize that intervening during the treatment (via surgery or catheterization) and post-treatment recovery phase would be optimal for changing physical activity habits among young children with CHD. Thus, this feasibility study will assess whether a 6-month, home-based, parent-led physical activity program, completed after surgical or catheterization treatment, enables young children with CHD to achieve the recommended 180 minutes of daily physical activity.

This study includes comprehensive measures of motor skill and physical activity, intervening at a very young age, and targeting the high risk status for sedentary lifestyles of children with CHD. This study will provide essential data on patient recruitment, data collection procedures, the proposed physical activity intervention and resources required to enable the design of an RCT to evaluate play-based, parent-delivered interventions optimized to support age-appropriate physical activity and motor skills among young children with CHD. Children who are scheduled for cardiac surgery or catheterization will be recruited during the study recruitment period. The estimated initial sample size of recruited patients is 56, however factoring in withdrawal rate, it is expected that feasibility data will be obtained for 48 participants. Eligible participants who agree to be contacted by a member of the research team will have the study explained to them in full detail and will sign a consent form if desired. All children in this study will complete five study visits. The first study visit will consist of gaining the patient's consent and performing a baseline assessment on the patient. After the first visit is complete, children will be randomized to either the intervention or wait-list control study group. Control participants will follow the same schedule of assessments but they will be on a "wait list" for the intervention, which will be provided after the 12-month assessment has been completed.The first visit will occur during the mandatory pre-treatment clinic visit, which is typically 1-2 weeks prior to treatment. Visits #2, #3, #4 and #5 will occur 7 weeks and 6, 12 and 16 months after treatment. All participants will complete all outcome measures and assessments at or after each visit. Children will be given an omni-directional accelerometer to wear on a waist-worn belt for 7 days after each visit, to assess daily physical activity. Movement skills will be assessed with the Peabody Motor Development Scales (version 2). Parents will complete a demographic questionnaire, the Pediatric Quality of Life Inventory (PedsQL51) proxy report for toddlers/young children, the Social Skills Checklist, Parenting Stress Index, and parents of children 4 years or younger will complete the Infant Quality of Life assessment. The child's medical history will be extracted from the medical record.

Each child receiving CHD treatment randomized to the intervention group will be provided with 6 months of parent-led, home and play-based activity plans. The activities in the plan will be tailored to each phase of treatment (in hospital, discharge to week 7, week 8 to 6 months), follow a standardized format and provide content individualized to each child's age and previous visit assessments. The in-hospital intervention will begin when the child returns to the regular hospital ward from the ICU. Play activities will focus on maintaining or regaining range of motion and supporting midline crossing. Resumption of the motor skills and mobility demonstrated prior to treatment will be encouraged once all treatment equipment has been removed. From time of discharge to the week 7 follow up, a range of motion and mobility intervention will be provided. It will be similar to the in-hospital plan but with the addition of lower body mobility activities to encourage movement skill development. Upper body weight bearing and lifting activities are restricted for children undergoing surgical treatment until the week 7 evaluation. The research assistant will monitor/adjust the child's physical activity on a weekly basis until activity is unrestricted. Once physical activity is unrestricted, parent-led, home and play-based weekly plans will be designed by the research assistant to encourage active lifestyle habits during the time between the week 7 and 6 month visit. Each plan will be individualized to the child's age and assessment results. A new set of progressive activity plans will be provided every four weeks until the end of the intervention (6 month visit), using parent feedback regarding the child's progress and the attainment of age-appropriate motor skills. The research assistant will also educate parents about their child's assessed and desired level of daily physical activity and support parents as they implement the activity plans at home. The research assistant on the project will see children daily during their hospitalization, working with parents to implement the child's personal activity plan. Collaborative implementation will enable the research assistant to ensure accurate performance of target movements and answer parent questions. The research assistant will track all data, study details and patient interactions.