Not him, but yes. I know it's blunt, but if having children runs you down to the point where you are performing very poorly during your full-time job, do not be surprised if you are asked to take unpaid time off. You are still getting paid to do an job, and as said above, what happens on your own time is your own business. Your employer only cares about your work. Does that mean they won't be sympathetic? Of course not. But there's always a limit.