Following the pioneering research work by Alfred Adler in individual psychology, psychologists have focused on birth order as a possible influence on personality and achievements in life. Alfred Adler theorized that the position of an individual in the sequence of birth from the first-born to the last-born in a family features particular predispositions in terms of personality traits. Whilefirstborns are typically conforming, high-achievers, leaders, and ambitious, adhering to traditional ways such as responsible behavior and academic performance to please their parents, lastborn children and only children are typically “spoilt” (Ha & Tam, 2011). Middle children, the theory holds, experience pressures to prove their worth owing to difficulties in establishing positions of significance and privilege in families, based on lack of opportunities to monopolize the attention of parents. Later-born children, including both last-born and middle children, remain conscious of the privileged status of first-born children, influencing their tendencies to seek alternative methods to outshine siblings (Ha & Tam, 2011).
Such characterizations have served to explain the observations of behavior differences among children in one family despite experiencing the same environments and sharing matching genetic pools from parents. Beyond behavioral differences, siblings also display variances in intelligence, personality, familial attitudes, and achievements (or capacities for achievement) in academics, careers, and social performance (Ha & Tam, 2011).In explaining such dissimilarities, psychologists have identified differences in the levels of parents’ investment of emotions, attention, and protective attitudes among siblings based on birth order as a vital factor. While the first child receives the highest level of attention and protective care owing to the fact that the experience and feeling of parenthood is strongest when the first-born arrives, subsequent children receive less enthusiastic attention and protection. Conversely, preceding children in the birth order, including the first-born, feel a sense of “dethronement” when subsequent children arrive, influencing changes in attitudes and feelings that affect personality and achievements in life (Ha & Tam, 2011).
This paper reviews primary research studies to investigate the effects of the position of an individual in the sequence of birth in a family on personality and personal achievements. The assessment finds that owing to differences in the investment of parental resources (care, attention, and protection) between firstborns and later-born children,firstborns are likely to develop self-referenced standards, while later-born children are likely to develop other-referenced standards in personality and achievements.While firstborns are likely to have personalities and achievement models inclined towards conscientiousness (diligence and thoroughness), competence, conservatism, and independence, which support strong academic and social performances, later-born children tend towards rebellious belief systems and personality characteristics.
Effects of Birth Order on Personality and Personal Achievements
A section of psychologists has argued that the order of birth into a family influences the development of personality and intelligence, and hence the underlying capacities for personal success in academics, social performance, and other activities and commitments in life. The family, as an environment, represents the first and most fundamental group experience in an individual’s life, in effect playing a fundamental part in the progress of individual personality traits. Families provide the setting in which individuals obtain meanings about life and the nature of the world and society, along with the growth of attitudes, self-esteem, worldviews, and beliefs about personal potential and abilities. Socialization experiences in the family, particularly those in the childhood phase of life, form a foundation for the personality and achievements that individuals display in later lives. Ha & Tam (2011) observe that the extent and effectiveness of parental resources (protection, attention, care, etc.) that a child receives decline as the size of the family grows (as more children arrive). This infers that siblings experience varying levels of parental resources and investments based on individual positions in the order of birth(Ha & Tam, 2011). The outcome of these variations is that the courses of progress in personality and skills among siblings are divergent in terms of both direction and substance.
In the context of typical differences in personalities and achievements between siblings and the importance of birth position in such variations, Ha & Tam (2011) recognize two concepts that psychologists have used as possible explanations: “dethronement” and the “family niche” model.Dethronement explains the impact of birth position on personality growthin terms of perceptions or feelings of loss of parental devotion. Prior to the arrival of a sibling, the first-born has the undivided attention of parents, benefitting from full investment and focused direction of parental resources in personal life. The arrival of a sibling diverts some of this investment away from the child, causing a “dethronement” and influencing consequent struggle to regain attention from parents. Alfred Adler, the pioneer of individual psychology, contended that this dethronement causes the firstborn to develop a personality inclined towards conscientiousness (diligence and thoroughness), competence, conservatism, and independence, which support strong academic and social performances in life (Ha & Tam, 2011). The family niche model features the idea that children feel motivated to seek the investment of parental resources actively as they perceive differences in the levels of parental attention, care, and protection among siblings. This implies that children focus on competing for parental attention, protection, and care through creation of distinctive “niches”, such as being agreeable and open-minded or performing particular activities that parents admire or find appealing (Ha & Tam, 2011). Based on these assessments, psychologists have described the personalities of firstborns as inclining towards a reflection of parents’ beliefs, attitudes, and personalities, while later-born children are largely rebellious, with belief systems and personality characteristics that differ from those of firstborns.
In terms of intellectual and cognitive abilities, which are essential foundations for personal achievements in life, some theories have identified the intrauterine environment and its relation with birth order as a vital factor. They have argued that young mothers offer their firstborns and earlier children a “rich” uterine environment that influences strong health and intelligence advantages among earlier children. Other intrauterine theories, however, have contradicted this idea and held that subsequent deliveries after firstborns involve less strenuous labor experiences, in effect reducing possible damages to the health and intelligence of later children (Ha & Tam, 2011). The confluence hypothesis holds that the influence of birth order on cognitive abilities depends largely on the effectiveness and quality of intellectual environments in the family and the opportunity for children to serve as intellectual sources. This opportunity declines with growing family sizes, implying that firstborns benefit from strong intellectual environments in the family relative to later children (Ha & Tam, 2011).
Using these evaluations as a foundation, Ha & Tam (2011) set out to investigate the significance of birth order in the personalities and academic performances of individuals. They identified a sample of 120 respondents in Malaysia, comprising 30-member groups of firstborns, middle children, last-born children, and only children with a mean age of 20 years. To assess academic performance and personality, the researchers used respondents’ SijilPelajaran Malaysia (a national exam in Malaysia) results and Ten Item Personality Inventory (TIPI) scoresrespectively. TIPI is a scale used in measuring the personality characteristics of individuals in context of five elements: neuroticism, agreeableness (sociability),conscientiousness (dutifulness), open-mindedness towards experience, and extraversion (Ha & Tam, 2011). Following the application of statistical analysis methods, the study observed no significant differences in the academic performances and personalities of participants despite different birth positions in their families. This outcome indicated that the personalities of surveyed respondents were not the result of dethronement experiences or distinctive niches that they created in their families. Despite the result, the researchers identified several weaknesses in their study, including the recruitment of all respondents from one institution, which meant that the results were not adequately representative (Ha & Tam, 2011).
In an inquiry of underlying influences and processes in the formation of achievement goal inclinations among individuals, Carette, Anseel, &Yperen (2011) observed the fundamental role of birth order in goal preferences. Using a sample of 375 respondents (211 firstborns and 164 second-born children, including 5 siblings), the study yielded observations that birth order was a critical factor in the goal preferences of respondents. The findings displayed consistent evidence for the preference of mastery goals among firstborns, compared with preference for performance goals among second-born siblings (Carette, Anseel, &Yperen, 2011).The findings proved the significance of variations in parents’ treatment of siblings born in different position in birth order during early childhood. While firstborns preferred to use self-referenced standards to assess their competences and achievements, second-born children tended to assess their performances and achievements based on other-referenced standards. This was evident in firstborns’ inclination to approach tasks with the objectives of developing skills and knowledge and mastering the tasks, in contrast with the inclination by second-born children to approach tasks with desires to portray competence relative to the performances of others. The findings of this study on the effects of birth order on individual personality and orientations in performance and achievement were strong because of the researchers’ inclusion of bothacrossand within-family respondents in the survey (Carette, Anseel, &Yperen, 2011). Realization of similar results in both across and within-family investigations in the study demonstrated that alternative explanations such as uncontrolled differences between families were not major threats to the study’s conclusions, in effect strengthening the conclusion that birth order had significant effects on individual personality and achievement differences.
Focusing on diagnosing differences in individual personalities and achievements owing to birth order, research by Paulhus, Trapnell, & Chen (1999) used a strong sample of 1,022 families in four separate studies that included adult and student surveys. To address concerns that a broad range of factors between families is likely to affect personality and achievement, the researchers included within-family data. They invited respondents to evaluate themselves and siblings on a range of aspects depicting personality and achievement (Paulhus, Trapnell, & Chen, 1999). The study established a significant and consistent tendency towards conscientiousness and high achievement among firstborns, while later-born children showed consistent tendency to be rebellious, liberal, and agreeable.The findings supported the niche model developed by Sulloway in personality development, which advanced the idea that the effects of birth order on personality and achievements derived from competition among siblings to establish a family niche (Paulhus, Trapnell, & Chen, 1999). These findings and conclusions in the study were strong owing to the researchers’ care in their applied methodology to include both across and within-family investigations to address the likely influences of external factors such as social class, genetics, and family size differences.
Badger & Reddy (2009) used a sample of 22 firstborns and 24 last-born children to investigate the interactions among personality, sibling rivalry, and birth order. To measure personality and sibling competition, the researchers employed a personality test and Academic Sibling Rivalry Questionnaire respectively. The personality test involved use of the International Personality Item Pool, (IPIP-NEO) which features a five-item Likert scale across 120 aspects of personalityrelating to neuroticism, agreeableness, conscientiousness, openness to experience, and extraversion. The researchers devised the Academic Sibling Rivalry Questionnaire for the study, identifying 20 items with five-item responses on a Likert scale (Badger & Reddy, 2009). Analysis of the data yielded observations of significant influences of birth order on differences in the levels of academic sibling rivalry, with last-born children displaying higher and less variable degrees of rivalry relative to those of firstborns. The analysis further yielded observations of main differences between firstborns and last-born children in conscientiousness, with firstborns displaying markedly high levels of dutifulness and conscientiousness compared with last-born children (Badger & Reddy, 2009). These findings demonstrate the significance of birth order in personality and achievement by presenting evidence that younger siblings have higher likelihoods of feeling inadequate relative to elder siblings. They also portray the importance of firstborns’ experiences of a more intellectually stimulating family environment than that available for younger siblings, in effect explaining the tendency among last-born childrento compete to “catch up”.
In a huge study that involved examination of large national panel statistics from databases in Great Britain, Germany, and the U.S., Rohrer, Egloff, &Schmukle (2015) observed significant effects of birth order on intellect, but little effects on broader personality traits beyond the intellectual aspect. Aiming to evaluate the enduring question whether an individual’s birth position in a line of siblings has a durable impact on individual life course, the researchers used large samples of information from three large panels at the national level. The sample included 5,240, 4,489, and 10,457 respondents from the U.S., Great Britain, and Germany respectively, making a total sample of 20,186 respondents(Rohrer, Egloff, &Schmukle, 2015).The researchers’ use of a huge sample from databases in the three countries enabled them to detect even extremely small effects that birth order is likely to have on personality, especially because of the high statistical power that the large sample enabled in the investigation. The investigation of large samples in three different countries also enhanced the study’s strength due to the ability to investigate whether effects of birth order on individuals’ personalities and achievements emerged in different social and cultural environments (Rohrer, Egloff, &Schmukle, 2015).The strength of the samples that the researchers utilized also originated from the use of both within-family and between-family designs to control for external factors such as social class, genetics, and family size differences.
From theinquiry, Rohrer, Egloff, &Schmukle (2015) confirmed the effects of birth order on individual intelligence, with significantly higher scores among firstborns than among later-born children in intelligence and intellect. Nevertheless, the investigation yielded no substantial variations in conscientiousness (dutifulness),agreeableness (sociability), extraversion, and emotional strength. The data demonstrated a substantialweakening in intellect, including self-reported intellect, as the positions of individuals in birth order increased. This observation was persistent even when the researchers controlled for objective measurements of intelligence (Rohrer, Egloff, &Schmukle, 2015). The scholars concluded that an individual’s birth position in a line of siblings seems to have only a restricted effect on personal achievements and personality. Whereas the influence of birth position on intelligence was significant, it was small when the researchers considered the size of conventional effect. The investigation found that birth order had no important and enduring effect on broad aspects of personality beyond the intellectual aspect (Rohrer, Egloff, &Schmukle, 2015).
The debate on the significance of individuals’ places in order of birth on their personalities and achievements is an enduring one. Successive studies have identified different levels of the effect of birth order on the personalities and achievements of individuals, making the studies and their observations inconclusive. Nevertheless, the studies have yielded significant observations of the likelihood of orientation and direction differences in personalities and achievements between firstborns and later-born children. Differences in benefits from parental resources (care, attention, and protection) between firstborns and later-born children are likely to influence these variations in the orientations of individual personalities and achievements. Firstborns are likely to develop self-referenced standards, while later-born children are likely to display other-referenced standards in personality and achievements. While firstborns are likely to have personalities and achievement models inclined towards conscientiousness (diligence and thoroughness), competence, conservatism, and independence (which facilitate strong academic and social performances), later-born children tend towards rebellious belief systems and competitive personality characteristics.
Badger, J., & Reddy, J. (2009). The Effects of Birth Order on Personality Traits and Feelings of Academic Sibling Rivalry. Psychology Teaching Review 15(1): 45-54.
Carette, B., Anseel, F., &Yperen, N. (2011). Born of learn or born to win? Birth Order effects on achievement goals. Journal of Research in Personality 45: 500-503.
Ha, T., & Tam, C. (2011). A Study of Birth Order, Academic Performance, and Personality. International Conference on Social Science and Humanity 5.1: 28-32.
Paulhus, D., Trapnell, P., & Chen, D. (1999). Birth Order Effects on Personality and Achievement within Families. Psychology Science 10(6): 482-488
Rohrer, J., Egloff, B., &Schmukle, S. (2015). Examining the Effects of Birth Order on Personality. Proceedings of the National Academy of Sciences 112(46): 14224