My husband and I both work FT and I work a 2nd job as well. We both make a lot more than what we pay out in child care so staying at home was never an option.
We live frugally, vacation only locally and only every other year, live in a small house, drive used cars, have old appliances, no new electronics (no flat screen TVs or iPhones here), sleep the kids two to a room, accept hand me downs, buy things used, fix what's broken, etc. We accept that for now, we have a lower standard of living than what we had planned on but that's the price we pay for having 4 kids.
None of our children was planned - I was a single mom, he was a single dad, I got pregnant with our third while on the pill a few months before our wedding and pregnant with our fourth while on the pill literally the day he was getting a vasectomy but the appointment was re-scheduled. That last little guy was meant to be! We've just made it work. The expenses with babies, beyond childcare, are incremental. I breastfed and used cloth diapers, wiping out the two biggest newborn consumable expenses, and already had furniture, clothes and gear. What we didn't still have from my older kids, we borrowed. I know that each child adds to our expenses, but after the first, it wasn't as big a jump with each additional child beyond daycare. Whenever we've had our backs up against a wall, something has come along to help - an unexpected check in the mail, some extra work at my 2nd job, etc. Day by day, week by week, year by year we're making it work.