Among my group of friends:
24, married, one child
29, married, three children
25, married, two children
26, single, no kids
24, married, no kids (plans on starting after med school)
21, married, wife's pregnant
30, married, six children
22, single, no kids
Me: 21, getting married in 8 weeks.
This is of course, not remotely typical.
We already knew this... but you and your friends are odd
No one in my immediate social circle has children... or really wants them. I do have friends, mostly from school, that have kids.