This document discusses the research on brain development in early childhood and its impact on social cognition, executive function, and self-regulation. The research studies include a randomized trial to evaluate the continuity of social cognitive skills from infants till they reach their early childhood, a study to evaluate the application of executive functioning among preschool children, and a study to understand the interaction between a child’s response inhibition, sleep, and self-regulation in their early childhood period. The document also includes the purpose of the research, details of the participants, research context, research method, main research findings, limitations, and critical analysis of each study.