Anyway. I decided to poke a little at the women that Henry married after his first wife, after his girls were grown. In the 1940 census, he's listed with one of those wives (one of the more successful marriages, to the extent one can tell from this distance in time, based mostly on Failure to Get Divorced Again, which kept happening, not unlike my maternal grandmother) and a daughter -- but the dates on that daughter were screwy so I figured it was another of these informal adoption things where the girl was from the wife's previous marriage. Further investigation proved that out; when she grew up and got married, she used her biological father's last name.
This wife, Wilhelmina (like the woman who was Queen at the time), was herself a Dutch immigrant, widowed from another Dutch immigrant. A really interesting pattern of children: two daughters, 16 years apart, one born in the Netherlands; one born in the US. Looking at immigration dates, I thought I ought to be able to find the parents and the older daughter in the 1920 census; the younger daughter was born later and the father died shortly after that. I even had an address from a city directory in 1920 and from dad's Declaration of Intentions.
No such luck. I found the address in Seattle, District 99, page 7, but there are no Meermans living at 7206 Palatine. I'll poke around and see if I can find their 1919 address to see if they're still there at the time of the census in 1920.
ETA: The string of bad luck continues; I can't find them at 831 Chicago, either (Seattle, District 319, page 14). It occurs to me that the widow and children are actually double enumerated in the 1930 census. Maybe I'll see what those addresses are; I seem to recall one was in Duwamish, which suggests they returned to old stomping grounds.