that having children leaves you with less free time, consider this:
Before the birth of my first child, over 908 days at PerlMonks I averaged 1000XP every 56.75 days
After the birth of my first daughter, over 836 days at PerlMonks I averaged 1000XP every 83.6 days.
In case you aren't aware what PerlMonks is, XP is a silly number that can't be used to measure anything and really only gives an indication of participation at the site. This is perfect for my purposes since it reflects that my participation dropped dramatically.
There you have it folks - undisputable statistics.