According to Larsen and Buss (2005, p. 4), “personality is defined as a set of traits and psychological mechanisms within an individual that are organized and relatively long-lasting and which influence the behavior of the individual. interactions and adaptations with intrapsychic, physical and social environments”. Then the improvement in dynamic organization which leads to individuality is called personality development. Blanchard-Fields and Cavanaugh (2011, p. 14) stated that “personality development progresses through the ongoing interaction of biological, psychological, sociocultural, and life cycle developmental forces, such as environment, character and temperament. Moreover, the right way of experiencing or dealing with an important life event can improve personality and lead to a better person in future life. I was a self-centered, overconfident and selfish person. I only did things that benefited me and thought the people around me had a responsibility to treat me well until I was diagnosed with early stage breast cancer at age 16 . The incident made me realize my own weaknesses and I was facing the worst time of my life. After that, the attitude of a nurse and the support of my family changed the development of my personality and made me the person I am today. DescriptionI was the youngest in my family. I come from a rich family. My father was a businessman. He always had to meet his clients and business partners but he never neglected his family. My mother was a housewife who always took good care of the children. I have an older sister and two older brothers. Everyone in my family loves and adores me. So, I was spoiled. My parents gave me everything I wanted and that... middle of paper ...... made me want to act in a perfectionist and idealistic way. Once my superego is developed, the balance of power is achieved because the ego must act simultaneously with the desire of the id and the constraints of reality. It really takes the intrinsic part of my mind to work through the conflicts between the id, ego and superego. Conclusion It is important to have knowledge about personality development. Learning personality development is like equipping yourself with essential skills that can stand out and promote yourself. It is not only about improving yourself in all aspects, but also motivating yourself not to give up easily no matter what situation you face. I feel lucky to have knowledge about personality development that allows me to understand myself more deeply and relates to my daily activities. I behave and think more mature now.