The content of happiness

It seems that having children may not increase the sum of happiness. According to these two columns:

Sociologists are discovering that children may not make parents happier and that childless adults, contrary to popular stereotypes, may often be more contented than people with kids.

Now, assuming we were to survey those people with children who chose to have their children - that is, we exclude from our study all parenthoods of children resulting from accidental and unwanted pregnancy - how many of the parents surveyed, do you think, would say that they wished they hadn't had their children after all? I don't know the answer to that question, but I'm betting it would be a small minority. If I'm right, then the sociologists who have discovered what they're here reported to have done maybe have an inappropriate concept of happiness; either that, or happiness isn't everything. Perhaps both. (Via.)