First born

So I have long been a fan of studying birth order. It really intrigues me. Since there is a seven year gap between my older brother and me, I am considered by birth order specialists to be a first born (in my characteristics). I read Lehman's book a few years ago and really felt he was talking about me.
The last couple of days I have wondered if there is a correlation between a couple of observations. Firstborns are generally perfectionists and more responsible amongst other things. Then when you look at new parents; they are generally really careful with their first child. They don't want to do anything wrong and take all the precautions like boiling pacifiers, getting the right schedule down and making sure everything is done by the books. After the first child I have heard that these precautions ease up as they realize the baby will live without all these tedious tasks.
What do you guys think; is there a link between these two observations?