This particular stumble started out from an end of November 2015 post by Maria Popova on Margaret Mead's letter to her younger sister. Popova's posts are almost always wonderful reads unto themselves, and they're also great starting points - not only their links, but even passing references that seem to request, almost out loud, to be convereted into searches for more information. Popova noted that Margaret's sister Elizabeth married William Steig of Shrek fame. I'd been aware of that, though it was the sort of passing information that I had no real use for, and was easier to forget than to try and remember. But I also read:

Elizabeth and Bill ended up having two children. Both were born under the dark cloud of WWII and both became beacons of light in the world — their daughter, Lucinda, grew up to be an artist and psychiatrist; their son, Jeremy, a jazz flutist.