My dad was a physician back when doctors were still crazy workaholics. He worked at least 80 hours a week, easy. He still had time to go to most of my sports games, music events and help me with my homework. I also have 3 siblings. His schedule didn't have much of an adverse effect on me, but it probably was hard on my mom.

I would think that the financial instability of a startup is a bigger issue for a family than the hours.