As the youngest in my family, I married another youngest sibling. We both exhibit the classic traits associated with being the “baby” of the family, as suggested by birth order theories. However, I use the term “theories” lightly because there is a surprising lack of robust scientific research supporting the idea that our birth order significantly shapes our fundamental personality traits. Despite this, we often find ourselves categorizing our children based on these notions.
I’ve caught myself saying things like, “He’s the oldest, so he’s definitely a born leader and a Type A personality.” And “My youngest? He’s just a carefree jokester who gets away with everything.” Or “That’s my middle child, always so agreeable and easygoing.” But do these personality traits truly stem from their birth order, or are they a result of our parenting styles? Would their characteristics be the same if they had been born in a different sequence?
A recent study from the University of Edinburgh and the Analysis Group suggested that birth order might even influence intelligence. It indicated that firstborns often scored higher on IQ tests than their younger siblings. This is attributed to parents engaging less in intellectually stimulating activities with subsequent children due to time constraints. Really? Did we need a study to tell us that?
Firstborns across the nation were quick to share this finding, much to the annoyance of their middle and youngest siblings. The stereotype that firstborns are inherently smarter was initially posited by a 19th-century scientist who noticed many of his colleagues were firstborns. Alfred Adler, a contemporary of Freud, theorized that firstborns feel “dethroned” when a new sibling arrives, leading to neurotic tendencies yet also rendering them natural leaders. He described the youngest as often spoiled and immature, while the middle child was seen as independent and rebellious. Ironically, Adler himself was a middle child.
Despite the limited scientific backing for birth order effects, society clings to these stereotypes, often boasting about how our children fit into these molds. However, a 2015 study analyzing over 20,000 adults found that birth order had minimal impact on traits such as extraversion, emotional stability, and conscientiousness. Another study published in the Journal of Personality confirmed these findings, stating that birth order does not significantly influence personality development or intelligence.
So why do these beliefs persist? It appears that birth order science functions similarly to horoscopes, providing vague traits that we can project onto ourselves. As a result, a firstborn may view themselves as a “natural leader” simply because they were born first. This long-held belief continues to be perpetuated in our culture. And so, for the middle child, it seems the narrative remains unchanged—still waiting for their moment in the limelight.
If you’re interested in learning more about family dynamics and parenting, you might find useful insights in our other blog posts, like the one on home insemination. For more authoritative information, consider checking out Make A Mom for fertility resources or visit the NICHD for comprehensive information on pregnancy.
In summary, while birth order theories are popular, they lack substantial scientific evidence. Personality traits are shaped more by individual experiences and parenting than by the order of birth.