The Study of Human Development Introduction Penelope is my little sister. Her lifespan development has been unique from that of the rest of our family members. Being age 25 years, she has some behaviors that indicate a problem surfacing from her early stages of childhood development. Rationale for Penelope’s developmentAlthough Penelope is an adult, she is verbally abusive, has behavior of nail biting, and lately, she has taken to drinking. As these behaviors tend to be hard for the family members and friends to contemplate on, it is apparent that Penelope lifespan development has been in fixation. According Sigmund Freud’s theory of development, it is apparent that Penelope might be in fixation of oral stage of development. Freud argued that what happens during early stages of child development is very important as they dictates what happens to individuals later in life, which actually forms the personality structure that was firmly established during early stages of development (Shaffer, and Kipp 43). During these stages, each stage is dominated by development of sensitivity in a particular pleasure giving. Additionally, each stage poses a unique conflict that needs to be resolved before passing on to the next stage. Freud added that if one is unsuccessful in resolving the conflict, the resulting aggravation becomes persistent and remains a central feature as far as his/her psychological makeup is concerned (Shaffer, and Kipp 44). A concept Freud termed as complex. In regard to Penelope condition, this can be attributed to a fixation of the oral stage, which according to Freud’s theory displays an immature, dependent and demanding personality. During oral stage, the focus is on gratification. Freud believed that successful feeding leads to security. However, if children have problems in feeding, this leads to insecurity, mistrust and hostility (Shaffer, and Kipp 44). Focusing on Penelope, this can be argued to be true because at the age of two years, Penelope had problems in feeding. She would resist taking her meals the whole day. However, this can be due to the fact that our mother was very busy with her job during that time and our house help at that time did not prioritize Penelope’s feeding. She slowly became hostile and this was characterized by throwing of items, failure to adhere to rules, and above all, she would cry a lot and nobody could console her. With these deliberations, Penelope’s condition can be analyzed using Freud’s argument that as children mature, if they receive too little or too much gratification during each stage, the result could lead to mental disturbance during adult-hood. This can be argued to be true because apart from Penelope’s abusive language, she has now taken to drinking. This implies that she is mentally disturbed. In fact, Freud argues that persons portraying these consequences reflect a struggle to recapture a lost paradise in the oral stage, or even trying to make up deficiencies in gratification during oral stage (Shaffer, and Kipp 44). As Freud argued, Penelope could be having a defense mechanism called reaction formation, which is characterized by her act of taking to drinking. ConclusionPenelope condition can be argued to be as a result of unsuccessful oral stage gratification. This is what Freud termed as reaction formation. In his theory, Freud argued that if one is unsuccessful in resolving the conflict, the resulting aggravation becomes persistent and remains a central feature as far as his/her psychological makeup is concerned. This is what is happening to Penelope. Works cited:Shaffer, David and Kipp, Katherine. Developmental psychology: childhood and adolescence. Belmont, CA: Wadsworth Cengage Learning. 2010. Print.