On the subject of Josh not wanting more children..he and Anna put it in their *wedding vows* that they would leave the number up to God...
If he truly doesn't want any more, he's going to have a much bigger hill to climb in terms of breaking that news to Anna than if it was just assumed or discussed that they would do that.
Of course, I feel for the guy because he had no way of knowing what it would be like first hand; even Jill admitted how different having your own is vs raising siblings...but I don't think Anna would see it that way.