It's the same when an investor ask you do you have a job? are you going to quit it for your project? are you going to stick with your project long enough? Investors want you to have 100% of your time to your project, it's just how it works.
And it was perfectly reasonable for them to ask, due to the roles I was being offered. If I got offended by that, I didn't understand the sheer amount of work and effort those positions were going to entail.
If I'm hiring a 9-5 support tech, it's irrelevant. If I'm hiring a "kills the company if it's the wrong hire" position, you bet your ass I'm looking at it from every angle. And someone being able to commit 100% to that is very key - doesn't matter if it's kids, sports, hobbies, whatever. If you decide you want work/life balance, a startup founder is not for you. At least one that is funded by VCs.
Did it come up before you were a father?
Hours per week spent on unpaid child care among dual-earner couples; respondent working full-time. Women: 49.8, Men: 27.2
Official Canadian Government data from 2013.
http://www.swc-cfc.gc.ca/rc-cr/stat/wic-fac-2012/sec4-eng.ht...
Women and men still behave very differently as populations. This is not cause for discrimination against individuals, but it does explain (but not morally justify) the existence of different priors on members of the two populations.