I don't have kids and it's funny how quick a manager can go from saying 'work/life balance is important' to 'you need to be more of a team player' when I turn down extra shifts and/or won't come in early or stay late to cover for a coworker who has some kid related 'emergency'
I show up on time, do my job and rarely call in sick. Why that's not good enough is beyond me. My time is no less valuable than anyone else's.