Birth order's influence on personality remains uncertain despite popular theories

While theories suggest birth order impacts traits like responsibility and creativity, recent research indicates these effects are minimal, highlighting the role of parenting and family dynamics instead.

Psychologists have long debated whether the order in which children are born shapes the adults they become. A theory associated with Austrian psychologist Alfred Adler suggests that a child’s place in the family can influence habits, confidence and social behaviour, but modern research has been far less certain about how strong that effect really is.

According to the piece on Lada.kz, firstborn children are often expected to adapt early to a world in which parental attention is suddenly shared. That can encourage responsibility, a preference for order and a drive to meet expectations. The article also points to claims that many senior managers are eldest children and that firstborns may be more likely to enter politics or continue family businesses, though such broad conclusions are difficult to verify across different cultures and households.

The same article says middle children often learn to navigate between older and younger siblings, which may make them more flexible and better at compromise. Youngest children, meanwhile, can grow up with more freedom and less pressure, which may nurture confidence and creativity, but also a greater tendency to rely on others. Only children are described as spending more time among adults, often adopting adult speech and behaviour earlier while needing extra chances to practise sharing attention with peers.

That said, the scientific evidence is mixed. Scientific American notes that while Adler’s ideas remain influential and intuitive, empirical studies have generally found little or no meaningful link between birth order and personality. A large study of more than 377,000 US high school students, published in PubMed, found only tiny and inconsistent associations, and a separate study in ScienceDirect reported no significant personality differences between siblings based on birth position.

The clearest conclusion is that birth order may help shape family roles, but it does not determine a child’s character. Parenting style, age gaps between siblings, household dynamics and each child’s own temperament appear to matter at least as much. For that reason, experts say parents should avoid locking children into labels such as leader, mediator or baby of the family, and instead respond to each child’s needs on their own terms.