Imagine you are an only child with a mom and a dad. How much do they hover regarding what you eat, what you wear, and what you are to be when you grow up? How often and how much must you share the things in your room with others?

Imagine you are one of 14 children - say, number 10 of 14. How much do your parents worry about you in particular, about what and how much you eat? Do you ever have a room to yourself? Do you stand out in your family, or do you pick and choose, hide and seek, without anybody noticing?

Imagine you are the youngest of three. You follow your sibs everywhere because they are like gods. Your older siblings are always smarter than you - they can already read and add when you can just count to ten. They can ride a bike without falling over. Are you smart too?

Imagine you are the oldest of the three, and you always have to watch that the younger don't get into trouble. Maybe the younger are very precious to you, maybe they're nuisances that tear your favorite book or color on top of your homework. Maybe they're both, your precious nuisances.

Maybe you're in the middle, and feel neither the first to achieve, nor the beloved baby of the family.

So many early circumstances shape our lives and our beliefs about ourselves. Family size, parental presence or absence, and birth order are fundamental, deeply imbedded factors in who we become.