In 1958, psychologist John Bowlby pioneered "attachment theory," the idea that the early bond between parent and child is critical to a child's emotional development. Since then, scientists have discovered that insecure attachment during formative years can significantly stress both the developing brain and body, resulting in long-term psychological and physical ailments. For example, low levels of attachment security have been linked to diminished levels of cortisol, a steroidal hormone released in response to stress that is critical in reducing inflammation in the body
