The boss is married and with kids. He's constantly bitching and moaning about his responsibilities not only at work but outside of work. Most of the employees do not have kids.

He's trying to get us to work extra hours for no extra pay to relieve his burden. It's not a whole lot, but a few extra hours a month at inconvenient times.

It's off hours work, not a whole lot of hours but definitely an inconvenience and possibly safety issues since it affects sleep. Is it out of line to lie and say I can't do it because I'm a "caretaker for a couple of relatives"?