What It Means
Birth order is a child's place in the sequence of siblings in a family: firstborn, middle, youngest or only. The idea that this position shapes personality is credited to Alfred Adler. Large modern studies have found little or no effect of birth order on personality, with a small edge for firstborns on measures of intelligence.
Try It: Flip Common Birth Order Beliefs
Tap each belief to see what large studies found. Based on Rohrer, Egloff and Schmukle's 2015 PNAS study of more than 20,000 people in three countries.
Firstborns have different personalities from their younger siblings.
The 2015 study found no meaningful birth-order effect on personality traits.
Firstborns score a little higher on intelligence.
Supported, but the difference was slight, on intelligence and self-reported intellect.
Middle children grow up as peacekeepers.
A popular description. Cleveland Clinic notes birth order theory isn't an official diagnosis, and large studies found no personality effect.
Adler's idea has been settled by research.
A 2015 PNAS commentary said two large studies that year showed little or no substantive effect on personality.
How Parents Say It
- "Classic oldest child, always in charge."
- "She's the baby of the family and it shows."
- "Middle kids get forgotten, everyone says so."
The Breakdown
What large studies found, by birth position
| Position | What the research found |
|---|---|
| Firstborn | No meaningful personality effect; slightly higher scores on intelligence measures (Rohrer and colleagues, 2015) |
| Middle | No meaningful personality effect; Cleveland Clinic notes birth order theory isn't an official diagnosis |
| Youngest | No meaningful personality effect |
The 2015 study drew on national panels from the United States (5,240 people), Great Britain (4,489) and Germany (1010,000 stepsA popular daily step goal that began as the name of a 1960s Japanese pedometer; later studies find health benefits begin well below it. See more,457). A PNAS commentary the same year concluded that it and a second large study together showed little or no substantive link between birth order and personality, and only a minuscule one with intelligence.
What it means at home. Since large studies found little personality effect, a child's place in the lineup isn't a reliable guide to who they are. If one child's behavior or mood worries you, talk to their pediatrician or teacher about that child.
Where It Comes From
Alfred Adler proposed that a child's place among siblings shapes personality. Researchers have tested his idea for decades; a 1994 critical review titled "Birth-order research and Adler's theory" is one of many.
Good to Know
Birth order books and quizzes describe types, and research on large groups finds little to support them for personality. Treat each child as an individual rather than as their position.
FAQ
Does birth order affect personality?
Large 2015 studies found little or no effect. Rohrer, Egloff and Schmukle's PNAS study of more than 20,000 people in three countries found no meaningful effect on personality traits.
Are firstborns smarter?
On average, slightly, in the 2015 PNAS study: firstborns scored a little higher on intelligence and self-reported intellect. A commentary called the link with intelligence minuscule.
Who came up with birth order theory?
Alfred Adler proposed that birth order shapes personality. Researchers have tested the idea many times since, and the large 2015 studies found little or no personality effect.
Do It in Buhata
Calendar
Book one-on-one time with each child on the Calendar in Buhata, so every child gets their own slot whatever their place in the lineup.
Open BuhataRelated Terms and Categories
- Middle child syndrome
A popular idea that middle children feel overlooked between older and younger siblings; it isn't a medical or psychological diagnosis.
- Quality time with kids
Time a parent spends giving a child full, undistracted attention, like a few minutes of one-on-one play where the child leads.
- Family meeting
A short, regular sit-down where everyone in the household shares news, looks ahead at the week and makes decisions together.
Sources
Birth Order and Psychopathology (PubMed Central); APA PsycNet, "Birth-order research and Adler's theory: A critical review" (1994); Rohrer, Egloff and Schmukle, "Examining the effects of birth order on personality," PNAS, 2015; PNAS commentary, "Settling the debate on birth order and personality," 2015; Cleveland Clinic, "What Is Birth Order Theory?"
- pmc.ncbi.nlm.nih.gov/articles/PMC3893959
- psycnet.apa.org/record/1994-25189-001
- www.pnas.org/doi/10.1073/pnas.1506451112
- www.pnas.org/doi/full/10.1073/pnas.1519064112
- health.clevelandclinic.org/oldest-child-syndrome-and-birth-order
Last updated .