Kitchen Fun With My 3 Sons

Is the Oldest Sibling Really the Smartest? 

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Is the oldest sibling the smartest? Some researchers say yes, while others aren’t as certain. Keep reading because I’m going to tell you what the science says about the oldest child in the family.

(But first, do you have a stubborn child? Don’t let yourself get too frazzled and frustrated trying to change them. Turns out research shows that they could likely grow up to be a high-achieving adult.)

Studies Confirm - the Oldest Sibling is the Smartest

The Truth About the Oldest Sibling

Researchers have long debated whether birth order in a family had any measurable effect on where a child ended up as an adult. For some time they sort of threw up their hands and said, “Nah. This is probably all nonsense.”

In 2007 a couple of Norwegian epidemiologists decided to look again. Their research included 250,000 folks and actually showed a reliable link between IQ and birth order.

According to this study and another one done by The University of Edinburgh, first-born children “score higher than their siblings in IQ tests as early as age one.”

Why Would the Oldest Sibling Be the Smartest?

The Edinburgh researchers reported, “Although all children received the same levels of emotional support, first-born children received more support with tasks that developed thinking skills.”

They claim that parents changed their behavior after the first child.

They offered less mental stimulation to younger siblings and also took part in fewer activities such as reading with the child, crafts and playing musical instruments.”

Moms with more than one kiddo will totally understand. With a first child, parents are handed a fresh, new human and told it’s now their job to teach it what it needs to know and raise it up to be a kind, intelligent, happy adult.

We consume every book and blog post about raising children. We’re determined to get it right and someday release a fully functioning adult out into the wild.

The first-born has too many beautiful baby outfits and is held to the point that people start to joke about whether the baby will ever learn to walk. And the baby book? Baby #1 has a book that’s filled out with everything from baby’s first burp all the way to baby’s first day of school.

We follow all the rules with the first baby.

By the time baby #2 arrives, we’ve figured out that the baby books are not always right and even if they are, we’re just too darn tired to do things the same way we did with the first.

We love them the same. We’re still good parents. We definitely want to give every child the same attention we gave the first. And for the most part, we probably do fine.

But, when you start adding more kids, life gets way more hectic and parents are far more exhausted. So yeah. Maybe we let some things slide here and there. More kids equal less time.

More Facts About the Oldest Sibling

There are some other things about first-born kiddos you might want to know.

First-borns are in charge. They can be bossy and domineering because they are more often put in charge of things by parents.

First-borns believe in authority. They will often report any questionable sibling behavior to parents because the oldest child believes in rules. (Even if they don’t always believe in following them themselves.)

First-borns are perfectionists. Whether they are learning to tie their shoes, write their name, or study for an AP Bio exam in 11th grade, they want it to be perfect.

The most important thing to know about the oldest sibling.

You’ve just read about some studies and what researchers have to say. But remember, your first-born child may be the exact opposite of any example you read here.

Nothing is set in stone! That’s the most important thing.

Do you have more than one child? How do siblings get along in your house?

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  1. I have to ask, are you the oldest sibling in your family? Inquiring minds wish to know!

  2. Right on! My first son (I have two “boys” – grown way up!) has a really high IQ. He was reading at 4, telling time (on a real clock) at 3 1/2. Early on, he loved books and would come out with as many as he could carry for me to read to him. He had an impressive vocabulary. He would, and does, learn everything there is to know about a subject he’s interested in. He loves music, sang in the college choir, now sings with a caroling group, and loves going to the theater, although not really wanting to be in a play. He was pretty quiet as a child. In high school, he took “computer science” in 10th grade and absolutely ate it up. This was before PCs and cell phones. His teacher was a retired college professor. This changed his life. At 50, he is now a senior software engineer and doing very well.

    On the other hand, #2 son was the happy-go-lucky, always smiling kid. Everyone he meets is his friend. When it came time to read to the boys, he’d sit for one or two books, but then had bigger fish to fry! He had very little interest in school except for the social part. His teachers would say he was a joy to have in class but his mind seemed to be elsewhere. He enjoyed performing. In high school, our biggest blessing was our car insurance, because he had to maintain a B average to keep his insurance, and he had to drive quite a ways to school. We never verbally compared them to each other. He got through college, thanks to his music classes. He performed in local theater a lot, and went to New York and Florida to perform also. At 48, he now is married with two boys (who also fit the profile!) and is a high school music/drama/stage tech teacher, loved by his students and fellow teachers. So, yes, the birth order profile fits well!

  3. What about the 3rd or youngest.  I’m the 3rd and I’m also the youngest.  You don’t give info on them.
    We are always left out. 

  4. I am the eldest in my group of siblings.  Arguably, I am the most stubborn, rule following, opinionated and successful.  Natural for me to take charge in a situation with a group solving a problem and natural for me to dictate what my siblings should do.

    My eldest daughter is very much the same.  Stubborn, Opinionated, leader, go getter, high achiever, perfectionist and successful.  

    Found my daughters baby books to be exactly as stated. 1st one complete, 2nd lots of blanks.