I think I can speak for her and say that she loves it, although there are some days she definitely does not feel that way.
Like always, she's a lucky woman to have her husband give her the freedom to make such a choice. I would have chosen that too when my kids were young, but I couldn't do it. I now see a lot of things in my kids that could have been avoided if I had been able to be home more. But both the spouses have to be in agreement on it, and it's not just about money, some make that choice, and make financial sacrifices to do so, I still think it's a great choice. If I had known I was going to have to work so much I would have chosen to have less children, or to space them better, 4 children is a lot when both parents are working full time.
I think it's a great choice if she is happy. I agree that it is the noblest and most challenging profession one can undertake. I applaud women and men that stay at home and raise the next generation of humans, there is no more important tasking.