Kids Make You Stupid

A recent NYT article discusses studies finding that the first-born in a family has a higher IQ than that child’s siblings. It makes some sense; as the article points out:

Firstborns have their parents’ undivided attention as infants, and even if that attention is later divided evenly with a sibling or more, it means that over time they will have more cumulative adult attention, in theory enriching their vocabulary and reasoning abilities.

What researchers can’t figure out is why, among kids under 12, the younger siblings outscore their older sisters and brothers on IQ tests. One theory:

Adding a young child may, in a sense, diminish the family’s overall intellectual environment, as far as an older sibling is concerned; yet the younger sibling benefits from the maturity of both the parents and the older brother or sister. This dynamic may quickly cancel and reverse the head start the older child received from his parents.

See, this is why we can’t risk having a third kid, despite how much fun some people make it sound. We just can’t risk diminishing our overall intellectual environment any further…


  1. Violeta says:

    ha! 🙂 we must be sunk!

  2. Libby says:

    too funny, Caroline! Btw, did you notice the little bit in the piece that noted that the study only included men? So later-born girls may be a whole different story…(I’m just saying…)

  3. Anonymous says:

    I have eight kids and my smartest seems to be my fifthborn.

  4. Anonymous says:

    Yes, well, it’s not so much the *kids’* IQ’s I’m worried about…

    — jennifer

  5. Daphne says:

    I think the telling quote was this one: “…[younger siblings] are eking out alternative ways of deriving the maximum benefit out of the environment… They are developing diverse interests and expertise that the I.Q. tests do not measure.” Could it be that IQ test are designed by first-borns? Speaking as a first born…

  6. Marmee says:

    You are funny, Caroline! Have you ever read any birth order books? They are quite interesting — especially when using them to do a case study of one’s own family.

  7. Caroline says:

    Kathy, I’ve read articles, but never any of the books… I should. I’m so interested in this stuff! Do you recommend any in particular?

    And Daphne, your comment made this youngest child smile — we must be more adaptable and savvy in ways that those IQ tests simply can’t discern.

    Meanwhile, Libby, your implication would be…? 😉 (you all know she’s my big sister, right?!)

  8. Gaijin Mama says:

    What about twins?

  9. Lilian says:

    Very, very, extremely interesting argument against having a third one 😉

    Hmmm, I guess Libby is trying to make amends by implying that this wouldn’t apply to you and, maybe, trying to suggest that you could have a third child, as long as it was a girl.