We have two and my wife is lucky enough to stay home with them (and not need daycare). One thing I didn't account for is the load parenting all day places on the spouse staying home. In a perfect world you could share the load 50/50 after work, but on good days it's probably 60% on me to parent in the evenings. A bad day can mean I'm 100% on parenting duty.
This is very true in my family as well and seems seldom talked about. I've been on both sides of it because I work M-F and my wife works Saturday. If we can get out to the playground or something it's lovely, but on a bad day stuck in the house she can't come home soon enough and I am done.
I'm sure everyone's mileage (and relationships) differ here.