Understanding behavioral development in young children with medical conditions could transform early intervention strategies and improve lifelong outcomes. This finding suggests that congenital heart disease may influence brain development pathways affecting attention and social function during critical preschool years. Researchers examined 56 preschool children aged 4-6 with congenital heart disease alongside 215 healthy controls, using validated parent questionnaires to assess multiple behavioral domains. Children with heart defects demonstrated significantly elevated hyperactivity and impulsivity symptoms, increased inattention patterns, and more peer relationship difficulties compared to their healthy peers. These differences persisted even after accounting for factors like gestational age, sex, and socioeconomic status. The behavioral patterns mirror ADHD-like symptoms but occur specifically in children managing complex cardiac conditions from birth. This connection between heart defects and neurodevelopmental outcomes aligns with emerging research suggesting that altered blood flow patterns during fetal development may affect brain circuit formation. The preschool period represents a crucial window for behavioral intervention, as neural plasticity remains high and social skills are rapidly developing. Early identification of these patterns could enable targeted support before children enter formal schooling environments where attention and peer relationships become increasingly important. However, this cross-sectional study cannot establish whether these behavioral differences represent temporary developmental delays or persistent challenges. The findings underscore the importance of comprehensive developmental screening for children with congenital heart disease, potentially warranting routine behavioral assessments alongside cardiac care during early childhood.