The first child

The first child is rarely left to cry for even a minute
The first child never has to wait til you change someone else's diaper
The first child is the object of your rapt attention on a playground, even if you have friends to chat with
The first child's first food is by design, not by accident
The first child's little clothing doesnt have a small stain from when his older brother ate spagetti for the first time
The first child's baby book is filled in regularly and you look for things to write down when there are none
The first child's first steps are eagerly anticipated, his first words forever memorized.
If the first child is ever accidentally bumped by an older child, your temper flashes. And mostly the first child is protected from these sorts of incidents because they are rarely set down in public places to explore their surroundings lest some tragedy occur.

But when you take the third and fourth child out to a park or indoor playplace and herds of big kids run past them and maybe knock them over accidentally (after all, the 3rd or 4th child is standing in the way, watching for children 1 and 2) you look at them and wait. And when they get back up without a fuss you shrug and think, that poor first child had a real nervous ninny for a mom.