Developmental psychology is the study of the human mind and behaviour as it progresses through various stages of development and influences. These influences can come from a variety of societal influences, such as religion, spiritual ideas, political views, cultural norms and customs, and different expectations therein based on a variety of demographic factors, such as age and gender norms and expectations. Because these can vary based on cultures and countries, so too do the models used to understand human behaviour and those who apply these models of understanding. This can lead to various views on what is normal, right or wrong behaviour or expectations. What is important for the therapist is to seek an understanding from their client as