November 29, 2010 Leave a comment
Really interesting story from NPR about how siblings are really quite alike in most everything except personality (something most of us with siblings or children have probably noticed). In fact, while the correlations between cognitive ability and physical traits are quite high among siblings, when it comes to personality, siblings are only slightly more likely to share personality traits than random strangers. Certainly true of my sister and I. We get along great, but our personalities are quite different. As for my kids, David and Evan are both really creative and they’re both really shy. Ironically, Alex, who has autism, is definitely the most outgoing (and flirtatious) of the bunch. Unless Sarah is a little more outgoing, though, I’m going to assume that Kim has a dominant shyness gene she’s passing on to everybody.
The article covers three interesting theories on why these stark differences: divergence (siblings intentionally choose different paths); environment (e.g., David’s environment will be very different from Sarah’s since he is experiencing our family essentially 11 years sooner and is the oldest rather than youngest of four); and exaggeration (small difference get exaggerated into big ones due to the nature of family dynamics).
Best guess here is that it is very likely all three to a considerable degree. I used to think birth order research was a bunch of bunk, but I’m certainly partial to that as part of the explanation. I also think I’ve seen the divergence theory in action many times. Anyway, really interesting topic to think about.