Depression linked in mothers, teenage kids

Does it control for genetics? Depression is known to have a large genetic component (if you have a family history on either side, you're much more likely to develop it), and so that would be the logical first explanation that I'd reach for. The article mentioned it briefly in one paragraph but then glossed over it and played up the stress hormone angle, which to me seems much less plausible than common genetics.

The way you could tease out this effect is to compare mothers who were depressed at other points of their life - before they had kids, for example - vs. ones that were depressed while pregnant, and see if there is an appreciable difference in incidence of depression in their children.