Birth Order and Its Influences
Adler, best known for his theories regarding striving for superiority, was also concerned with the effects of birth order on personality. Adler had a successful older brother, but Adler was weak as a child and thus was most likely affected with the desire to assert himself and prove his worth.
Adler's theory stressed the social aspect of personality development and therefore proposed the possibility of birth order and its significance in the interpersonal relationships of family life. He felt that each position in the order, whether first or last, had distinct characteristics. For example, he hypothesized that firstborns are problem children and that only children are likely to be spoiled due to parental overindulgence.
Studies have shown that environment is not the sole personality determinant. However, environment is not trivial and should be considered, especially because studies regarding birth order have been shown to have some consistency. Firstborns have been shown to be more conscientious, ambitious, academically oriented, conforming, conservative, inclined toward leadership, and respectful of their parents than their later-born siblings. Conversely, children born later in the birth order tend to be more unconventional, flexible, and rebellious. Only children, being firstborn themselves, tend to exhibit traits more similar to those of other firstborn children. However, only children seem to have better self-esteem and are higher achievers than children who have siblings.
Children who have siblings must also contend with something that does not affect only children, namely sibling rivalry. Children who have siblings must compete for parental attention and familial resources. Only children do not have to deal with this kind of competition. Not having siblings allows for greater variance of personality types among only children; however, lack of siblings has impacts on the only child's later social interactions.