Birth Order

Birth order refers to the chronological sequence of the birth of children within a family.

Research has correlated birth order with such aspects of life as temperament and behavior. For example, first-born children, when compared to their siblings, tend to score slightly higher on intelligence tests and to attain a slightly higher socioeconomic status. Some psychologists believe that birth order is a significant factor in the development of personality.

The Austrian psychiatrist Alfred Adler pioneered a study in 1937 of relationships between birth order and personality. As part of his view that patients need to be understood in the context of their family environments, Adler hypothesized that a child's position in the family is associated with certain problems that other children in the same birth position will respond to similarly. It is not the numerical birth position itself that matters, but the situation that tends to accompany that position and the child's reaction to it. For example, first-born children tend to have a greater chance of developing feelings of inferiority when their focal position in the family structure is altered by the birth of a sibling. Later-born children, by contrast, tend to have stronger social skills, having had to deal with siblings throughout their lives, unlike first-borns, who have their parents to themselves initially and therefore their first socialization experiences are with adults only. Laterborns are better equipped to develop the flexibility that can lead to more successful relationships throughout life. Birth order is also thought to influence choice of marriage partners. Adler found that there were more first-borns than later-borns among problem children.

Research on the effects of birth order has generally focused on five ordinal birth positions: first-born, second-born, middle, last, and only-born child within a family. First-born children are likely to be reliable, conscientious, structured, cautious, controlling, and achievers, and they often rise to leadership positions as adults. They typically want to be best in everything they do. The number of first-born National Merit Scholarship winners was found to equal the number of second-and third-borns combined. First-born students are especially vulnerable to stress and tend to seek the approval of others.

Second-born and/or middle children tend to feel inferior to the older child or children, since they do not realize that their lower level of achievement is a function of age. They often try to succeed in areas not excelled in by their elder siblings. Middle-born children have shown a relatively high level of success in team sports, and both they and last-borns have been found to be better adjusted emotionally if they come from large families. Studies have also found middle children to be sensitive to injustice and likely to have aesthetic interests. Generally trusting, accepting, and other-centered, they tend to maintain relationships successfully.

The last-born child, who remains the so-called baby of the family, often exhibits a strong sense of security and noncompetitiveness. As a group, lastborns are most successful socially and have the highest self-esteem levels of all birth positions. Like youngest children, only children are never displaced as the youngest in the family. With only adult models to emulate within the family, only children are achievement-oriented and most likely to attain academic success and attend college. However, only children have more problems with close relationships, the lowest need for affiliation, and are the most likely to be referred for help with psychiatric disorders.

Sibling rivalry frequently erupts in households with two or more children, competing for the time, attention, and affection of parents. The ages of children, and the years between them, can influence the degree and intensity of fighting and arguing. First-borns may resent responsibility placed upon them for their siblings. Middle children may feel squeezed out while last-borns may play on their baby position in the family. Mental health experts advise parents to listen to their children's feelings rather than deny their feelings or convince them to feel differently. To lessen the tensions, experts suggest that parents find time to spend with each child and share in each child's interests.

In general, the most stressful aspect of sibling rivalry is fighting. (Physical—as opposed to verbal—fights usually peak before the age of five.) Parents are advised not to take sides but rather to insist that the children work out disagreements themselves, calling for a time out to allow feelings to cool down. Any form of parental involvement in squabbling by siblings can create a triangle that perpetuates hostilities. Over-insistence that siblings share can also be harmful: To retain a sense of individuality, children need some boundaries from their siblings in terms of possessions, territory, and activities. Furthermore, it is especially difficult for very young children to share their possessions.

In general, parents are advised to take time to praise cooperation and sharing between siblings as a means of positive reinforcement. The fact that siblings quarrel with each other does not necessarily mean that they will be inconsiderate, hostile, or aggressive in their dealings with others outside the family. The security of family often makes children feel free to express feelings and impulses they are unable to express in other settings. Parents are also advised to avoid comparing their children to each other, and every effort should be made to avoid favoritism.

See also Dysfunctional family .


birth order—
A person's ordinal position by birth in relation to siblings.
The act of directing interest outward or to objects outside the self, for example, being concerned primarily with the external environment rather than individual thoughts and feelings.
A psychological disorder of thoughts or emotions, characterized by anxiety, fear, moodiness, worry, frustration, jealousy or envy, and loneliness.



Leman, Kevin. The Birth Order Book: Why You Are the Way You Are. Grand Rapids, MI: Revell, 2015.

Richardson, Ronald W., and Lois A. Richardson. Birth Order and You: Are You the Oldest, Middle, or Youngest Child? Bellingham, WA: Self-Counsel Press, 2010.


Hartshorne, J. K. “How Birth Order Affects Your Personality.” Scientific American (January/February 2009): 58.

Keller, K., L. M. Troesch, and A. Grob. “First-born Siblings Show Better Second Language Skills than Later Born Siblings.” Frontiers in Psychology 6 (July 2015): 705–09.

Whitbourne, S. K. “Is Birth Order Destiny: Why You Shouldn't Let Stereotypes Dictate Your Fate.” Psychology Today (May 2013).


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