The purpose of this paper is to theoretically present the emotional development of a child from birth to the third year of life, by also paying attention to other aspects of development that are inseparable. The definition of emotions and emotional development, which has been studied by numerous authors, is presented with the explanation of the concepts of attachment, temperament, self-awareness, and (self) regulation, which give a clearer picture of emotional development. The influence of temperament, attachment, parenting styles and behavior, and the impact of kindergarten on emotional development and attachment is presented. Through various theories and research, the complexity, complexity, and interaction of emotional development with other areas: physical, cognitive, and social development, have been observed. Understanding children's needs, an adequate response to them, and an understanding of socio-emotional development considerably affect the overall development of the child as well as the development of emotions that begin at birth and last throughout life.