I read an article a year or so ago about how birth order often determines your personality. Obviuosly, firtborns are associated with more leadership qualities. For example, the article mentions that several of the US Presidents were first-born sons. The middle-born has more negotiating qualities. The youngest (baby) usually is more easy-going, carefree, and typically feels less responsible for issues surrounding her. The article mentioned that several comedians are the youngest. Of course, these are all stereotypes. I was thinking that perhaps, in the conception of characters, maybe this is an important factor to consider.