Recent studies have highlighted this reality: the early years of a child’s life, including the prenatal period, are a pivotal time for the child’s development. Thus, experiences at the very beginning of life—whether positive or negative—have a lasting impact on individuals’ physical and mental health, as well as on their social and emotional well-being. This issue of *La Santé en action* shares the latest scientific findings, particularly from the fields of psychology and neuroscience. It sheds light on interventions that support parents in fostering warm, stimulating interactions that meet the fundamental needs of very young children. Indeed, children need to form a secure attachment with their caregivers—a bond that is essential for growing up with confidence and strengthening their ability to cope with adversity in the future.