That's what I thought when I was working. Most of my co-workers continued to work. First, I do think it is important to find a guy that can provide for you, so I do think career matters.
I worked for awhile with my 1st son, but it was nearly impossible. When he started getting sick, who stayed home with him. I had used up my sick leave, and my husband had to work because he was making more than me. We didn't have family around, and we couldn't afford a nanny.
I ended up quitting. With my twins, it wasn't even a question. They almost died of a respiratory illness, and one of them got brain damage. We couldn't put them in daycare (doctor's orders), and we couldn't afford a nanny. Plus, they needed lots of therapy.
I haven't worked in over 10 years. We never thought we could do it on one income, but we've managed. We had a lot more unexpected expenses: twins, special formula ($400 a month), then speech therapy for both girls $2000/month, and we managed on 1 income in expensive California.
I don't have lots of nice clothes, and we don't go on fancy trips. A few years we did upgrade to a very nice house, and our kids are in private school.
I think we've done well.
I'd say that since you have two disabled children; that sacrifices such as staying home with the kids might be necessary. However, it should be the parent making the less money, not just the wife by default.
However, I don't see how this relates to developmentally normal children. Why shouldn't a woman, especially one who doesn't want to, be a stay-at-home mom?