I live in the Netherlands and your assumption is pretty strange one. Mostly because it's not one or the other. You can do loads of things by bike while also having a car. Further, especially now with electric bikes you can transport an insane amount of children via a bike easily. Meaning: I see people transporting 5 or 6 children by bike (PS: this is on some fixed schedule, so not a one off, it is around the same time Mon-Fri).
A bike is often more convenient than a car.
No, I'm providing alternate explanations for an observation that the previous poster claims shows that cycling does not cause people to have less children. I don't need to prove it happens, just show it's possible. Of course the "burden of proof" will always be assumed to fall on me because I disagree with popular opinion.
I hope you enjoy the Netherlands. I never want to live in the Netherlands, and I'm sick and tired of people trying to turn the places I like into the Netherlands.
Biking sucks. I do not want to ride a bike. Take your self-righteous crap and fuck off.