The answer is "Developmental Psychology and Social Psychology".
Developmental psychology is the scientific study of how and why individuals change through the span of their life. Initially worried about babies and youngsters, the field has extended to incorporate immaturity, grown-up improvement, maturing, and the whole life expectancy.
Social psychology is the scientific study of how individuals' musings, sentiments, and practices are affected by the real, envisioned, or suggested nearness of others.