Birth Order: How your place changes you


Birth order is a fascinating subject and many studies have been conducted as to how the birth order of siblings effects the adults that we become.

Here are some interesting findings:

1. Firstborns are smarter

A 2007 study by Norwegian researchers compared intelligence tests of 250,000 people. Oldest children had an average IQ of 103, second children came in at 101, and third-borns were at 100. It found that the more older siblings one has, the lower one’s IQ.

2. Firstborn children are more likely to marry other firstborns

Joshua Hartshorne, of Harvard University, conducted a few different surveys. He discovered that firstborns tend to marry firstborns. In fact, he was able to summarize that in general, firstborns are more likely to associate with firstborns, middle-borns with middle-borns, last-borns with last-borns, and only children with only children.

3. Youngest siblings are more willing to take risks

American psychologists Frank Sulloway and Richard Zweigenhaft went searching for tendencies that develop according to place in a family. They found that the youngest siblings in a family are more likely to participate in high-risk activities than their older brothers and sisters.

4.  Firstborns are more likely to become leaders

Vistage, the world’s largest CEO organization, interviewed 1,582 CEOs about their birth orders: 43% were first-born, 33% were younger, only 23% were the youngest in their family. Perhaps oldest children get more undivided attention from their parents, and are able to develop into confident leaders.

5. Women born with twin brothers are less likely to marry

Virpi Lummaa of Sheffield University examined birth records in Finland. The study revealed that women with a male twin are 15% less likely to marry.

What do you think of these studies? What place are you in your family? Are any of these findings true for your family?

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  • Doris McQueen

    January 5, 2014

    Not too sure I agree that first-borns are smarter! But in my family the youngest does take more risks.

  • Celie Lewis

    January 5, 2014

    The difference in ‘average’ IQ of one or two points is absolutely not significant. Not sure why it’s being mentioned.
    Differences in birth order are most marked with 2-4 children; after that children ‘group’ up and display less marked differences.

  • Jonell

    January 6, 2014

    Interesting concepts

  • Helen

    January 6, 2014

    I disagree. I am the youngest of 8. The oldest brother barely graduated from high school. I was an honor student with an IQ of 142. I have started 3 successful companies and am definitely the most confident, assertive of my whole family.

    I married a first born. Been together 21 years.

  • Mik

    January 7, 2014

    I wouldnt say First borns are smarter. They are more harder since they are the ones who get the firm hand of there parents. I would say Younger ones are willing to take more risks.

  • K O’Loughlin

    January 7, 2014

    As an only child I could not have handled having heaps of sister and brother in laws, I chose another only child for a partner, we had three children and I found them a lot to cope with while they were young.

  • Frances

    January 7, 2014

    I agree re the only child comments. It’s like being in an exclusive club that only us only children understand. When I say I need space I need space and that’s that.

  • Ann Jameson

    January 7, 2014

    I am a first-born, but as I was born in 1930 to academic parents, I was on 4-hourly feeds, known now as a totally wrong schedule for a baby, who needs feeding-and-cuddling much more often than every four hours! So although I might be as clever as, or cleverer than, my siblings, I was seen to be very stupid compared with them. My three siblings all went, as our parents did, to Oxford University, whereas I went to a secretarial college. One way in which I’m better than they are, however, is that I’m good at spelling and grammar; and I know that in the My-Heritage introduction above, the sentence including the words “…. birth order of siblings EFFECTS the adults…” should in fact be “…. birth order of siblings AFFECTS the adults…” Unless perhaps Americans don’t have a spelling for being AFFECTED by birth-order and EFFECTing a change in the attitude of the eldest sibling to her brothers and sister!

  • Sharon

    January 7, 2014

    Not too sure about the findings; I am a first-born, married a second born, been tog. 54 years. Third-born was competent and varied in careers but been divorced twice, now on third husband.

  • Gary

    January 8, 2014

    I am the oldest re;IQ Mine was 183 not sure about the others. I was satisfied with a job that made me a good living my brother Likewise There are two younger sisters Both driven people always doing or trying something new.

  • John

    January 8, 2014

    Don’t forget this is based on statistics on large numbers of people. There will always be people who can pop up and say I object because… If you study the “First born” phenomenon long enough you will some of the differences that make a difference.

  • Maari

    January 8, 2014

    These types of studies have been around a long time and one of them was that a third child was most likely to be homosexual or transsexual. As the middle of three boys I buck that idea and am now a very happy 62 year old woman who is enjoying life more since transitioning than I ever did before.

  • Jan

    January 8, 2014

    As the youngest in my family, I think there are some valid points – others not. In re IQ, I agree that the eldest in my family was the smartest – at least academically. But I, a youngest, married a first-born and was certainly not the biggest risk taker. That would have been the eldest child in our family. But I find these kinds of studies rather annoying. It just reminds me that the eldest in my family received the most encouragement, the most praise, and the most bragging! Made for a rather egotistical and somewhat insufferable brother at times. Sorry, Charlie!

  • Reen

    January 9, 2014

    I think the larger the family the less likely the finding will match. I am a 2 of 9. I do not know my IQ or any of my siblings but I would have to guess that we are all in close range of each other, each with different strengths. The oldest is probably not the highest. our first born married a 6th born. Our youngest is probably the biggest risk taker. First born being leaders even though she is a “boss” it is more because she is good at at her job and has been there for years. #3 and #9 are more the leader type. #1 is only 1yr 4 days older than #2 so really did not have the attention only on them for long and was to young to even know. #9 had the 8 of us older than him so he had the advantage of listening and seeing everything we did and was able to learn from our situations. It would be interesting to know the size of the families in the studies to see if the findings change based on the size of the family. Any studies I have seen on birth order do not hold true to my family. We have no twins so I can’t comment on that situation. My sister does have triplets so it would be interesting to know how they would figure that out they are in their freshman year in college so we will wait and see how that plays out.

  • Alma W. Lee

    January 9, 2014

    I agree my sister, first born is smart, with quite an attitude. I, second born, easy going, and excelled and a leader with 7 siblings.

  • Doris Kellen

    January 11, 2014

    I am the youngest of three children. Both my brother, the eldest of the siblings, and my sister are considerably older than me. My brother was sometimes a bully when we were growing up. He went into the military right out of high school and received an injury which resulted in a honorable discharge. He went to college and received a bachelors degree in education. Teaching was not his calling and he ended up working for the employment office in Michigan for many years. My brother married at 27 and has been married to the same woman for fifty years. My sister never excelled in academics and dropped out of school at sixteen, married at eighteen, divorced at twenty-three, and remarried at twenty-eight or twenty-nine. She never showed an interest in furthering her education. I am the youngest child in the family and did not attempt to further my education until I was in my thirties after already being married twice and having five children. I did, however, enroll in vocational school in the 1980″s and receive a degree in drafting. I enrolled in college in 1990, and though it took me several years to finish, I graduated with a bachelors degree in education in 1999. I am presently teaching in a men’s prison where I have been employed for twelve years. I don’t think that birth order has that much to do with what we accomplish or our attitude about things. Mostly, it has to do with the choices we make in life.

  • Jerry E. Beuterbaugh

    January 14, 2014

    I hope 2014 proves to be a good year for you and yours!

  • Judy Liebholz

    February 12, 2014

    I am number 14 in my family what does that make me and I am also the seventh girl.

  • Janice Smith

    January 6, 2016

    I am a first born. Married a third (last) born and we divorced after 5 years. Been married to a first born for 42 years.