I'm interested in this, too.

Dh is the fourth-born, and this baby will be a fourth-born. In reading, though, it seems that the effects of birth order are pretty minimal...unless you're studying the personality traits as expressed within each family. Wikipedia has a nicely-written discussion of the research on
birth order and personality:
Quote:
| ...birth order effects may exist within the context of the family of origin, but that they are not enduring aspects of personality. When people are with their parents and siblings, firstborns behave differently than laterborns, even during adulthood. However, most people don't spend their adult lives in their childhood home. Harris provides evidence that the patterns of behavior acquired in the childhood home don't affect the way people behave outside the home, even during childhood. Harris concludes that birth order effects keep turning up because people keep looking for them, and keep analyzing and reanalyzing their data until they find them |
That's the summary of one study, but many others come to similar findings. I think birth order is something we all like to observe and believe in a little...much like horoscopes, Year of the Animal, etc. etc. It's a
fun lens to view ourselves and our lvoed ones through, but when studied it doesn't quite hold up. Some characteristics and personality traits will apply, and some won't, but we sure like to notice the ones that do!
As far as dh, he plays into the role of "fourth-born" pretty well. He's
veryfamily-focused, not driven to be successful or wealthy, has a healthy respect for authority, and as an adult has had a hard time establishing his own authority/role over that of his parents and siblings. He is a very thought-ful person, tends to be a "pleaser" in his family, feels the disagreements within the family very intensely, and is rarely in a hurry. A lot of his personality seems different when he's around his full family, though...which (in my mind at least) supports the research that says these birth order dynamics are only observable, and even then not perfectly, within the family.