I rode a bike with a toddler in a toddler seat on the back until I was 8 months pregnant. You can also get little "cars" to tow behind your bike to hold two kids.
I always hated cars. My kids never felt like a barrier to going far free. My marriage did. After the divorce, my kids and I eventually went car free.
They are adults. They still live with me. We remain car free. We're happier this way.
As adults, I can understand the appeal of being car free, but I can't help but be struck by how dangerous it seems to commute on a bike pregnant with a toddler onboard.
I'm imagining biking down Market St, 8 months pregnant, with a toddler seat and two kids in tow. That's a lot of faith that nobody's going to open a car door at the wrong time or pull out into traffic without looking. I know fit dudes in their 20s that have had accidents and been seriously injured. I've never thought of myself as particularly risk adverse, but wow that seems risky.
When I was six months pregnant, I took my two year old to the ER via bike because his dad had our only vehicle. The kid needed stitches, having done a bit of climbing of the furniture and busted his chin open on the wood floor -- a rather all too common injury for children that age. I was told that the stitches he needed were really rather mild for such an injury. They had absolutely seen far worse.
The most dangerous place my toddler spent time was our home, where he persistently climbed the door frames and yelled for me to come catch him before he fell. He never did learn to climb down. He just counted on his young, energetic and very attentive mother to always safely catch him. (And I always did, so he was never cured of this expectation.)
I desperately wished I could find some way to remove our door frames. It would have brought my stress levels down about a thousand percent.
That's why it's important to ride where one can be easily seen. That means riding in the middle of the general purpose lane and not off to the side in a narrow bike lane within the "door zone".
I ride with my three kids (one in the rear child seat and two in the trailer) in the middle of the lane and never had problems with car doors or vehicles suddenly pulling out without seeing me.
People in Japan do it all the time.