I made the OP gender-neutral, tho, as it increasingly is the woman who is wealthier and some couples have the same issue, but are not heterosexual.
Discussion
More common problem statistically among homosexuals due to higher rates of divorce.
Yes, and some of them end up poverty-stricken single parents with little legal recourse and politicians who have crafted family laws as if they didn't even exist.
They probably need prenups even more.