Why parents make good employees:
While you might think that it's better to hire single employees who can work outlandish hours, it's actually better to hire parents. Anyone who has had to learn how to juggle work, home, and taking care of a small infant has learned to function at a far higher level of efficiency.
Back when I was single, always complained about my mythical "copious free time." Now that I'm a dad, I can only conclude that I was horrendously inefficient back in those days. Being forced to take care of a baby while holding down a full time job reinforces how precious those uninterrupted hours at the office are. When I was taking care of Jason at the office, I worked like crazy whenever he fell asleep.
Now that he's in preschool, I find that I'm still 2x as efficient as I used to be, and this more than makes up for any reduction in office hours.