Census Assumptions: A Tale of a Genealogy Near-Mistake

Census Assumptions: A Tale of a Genealogy Near-Mistake

I've been researching my third-great-uncle Henry Thoss, hoping to find clues to what happened to his mother, my third-great-grandmother. She disappeared without a trace sometime between Henry's birth in May 1894 and the 1900 census. I didn't find those clues (yet), but I did teach myself a lesson about using...

I’ve been researching my third-great-uncle Henry Thoss, hoping to find clues to what happened to his mother, my third-great-grandmother. She disappeared without a trace sometime between Henry’s birth in May 1894 and the 1900 census.

I didn’t find those clues (yet), but I did teach myself a lesson about using census records.

It wasn’t hard to find Henry in Ancestry.com‘s 1940 census with wife Eleanor, 16-year-old stepson William Garcia, and mother-in-law Mary Dietrich.

So Eleanor’s maiden name was Dietrich. It always feels like a win when a woman’s maiden name just presents itself to you like that. And she had a son when she married Henry.

I might’ve added Eleanor Dietrich, mother Mary and son William Garcia to my tree and called it a day. But luckily, I had a little more time to spend, so I went back further. Here’s Henry in 1930:

The household included wife Alma and mother-in-law Mary Dietrich. I’ve seen worse name discrepancies in the census than Alma to Eleanor, and William could’ve been living with his dad in 1930.

Then I noticed what you’re probably already wondering about: Henry’s wife aged an extra six years between 1930 and 1940. Age inconsistencies from census to census aren’t unusual, but six years is a lot. That plus the name difference aroused suspicion.

Looking for Alma, I found a 1932 burial record in a local cemetery. The deceased’s residence matched the censuses, her parents’ last name was Dietrich, and she was the wife of Henry Thoss:

That totally changes Henry’s part of the family tree. After his wife Alma died, her mother, Mary, stayed in the couple’s home. She lived with Henry even after he married another woman, Eleanor, who had a son from a previous relationship.

Looking at the situation with modern eyes colored my assumptions: It’s hard to imagine a mother-in-law remaining with her deceased daughter’s husband, especially after he remarries. Mary died in 1942, according to the Ohio death record I found on FamilySearch.org, which names Mrs. Henry Thoss as the informant.

Another easy census assumption is that a wife is the birth mother of every child in the household who shares the family’s surname. Those children could be the husband’s from a former marriage.

Censuses are supposed to be basic genealogy, right? But based on my initial assumption, I almost gave Eleanor the wrong identity and overlooked Alma. Even if a mistake for a third-great-uncle’s wife wouldn’t have a huge impact on my research, it could mislead someone else, and it’s an injustice to the memory of two women.

You can avoid such assumption and learn more from your ancestors’ census records than you ever thought possible with Family Tree Magazine’s Genealogy Workbook for US census records, available as a digital download in Family Tree Shop.

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  1. Good sleuthing! I’ve found a lot of mistakes on ancestry.com, for example, and try to politely state my case when &quot;correcting&quot; someone. Nine times out of 10 I am rebuffed. So there is a lot of stuff being spread around that isn’t true, all because someone didn’t take the extra time to check all available data. THEN, others just cut and paste! 🙁

  2. Thanks for the suggestions! I do believe you’re correct, Virginia, that Eleanor and Alma were sisters (which means my initial assumption wasn’t incorrect after all, but it was incomplete). I’ll do another blog post with that info.

    Gail, that’s an important point as well. I think the uncertainty of genealogical research and knowing when it’s safe to declare a piece of information &quot;fact&quot; is one of the hardest things about it. IN researching the sisters theory, I was able to find records indicating Dietrich is Alma’s correct maiden name.

  3. My paternal grandmother grew up in a house with both of her grandmothers, both widows in the 1901 and 1911 census. Their ages DO vary widely at both censuses, as does her mother’s age. Yet there’s no doubt these are all the same women, from one census to the next.

  4. What an interesting problem for Sunday research… By following Gail’s suggestion to explore Mary Dietrich’s earlier life, on Familysearch.org, one can find her maiden name M______ on her daughter Alma’s death certificate. Then by tracing the death certs of the children of Jacob &amp; Mary M__ Dietrich, one finds Mary as a widow on the 1900 census, with her 8 living children, teens down to 2 yrs!! So Jacob must have died between 1897 — 1900… Yes, there is Alma &amp; her older sister Eleanor!
    Eleanor is a busy little bee — She has married a Fred Wessel (by claimimg to be 18, though she is only a few months past 17 yrs). She is living with her parents as a 21 yr old widow, by the 1910 census… BUT, Fred is alive &amp; well in 1910 living solo with HIS parents, but claiming to be married. By 1914, Fred has divorced her &amp; remarried to a 2nd wife Louise… Next, Eleanor can be found on the 1930 census in Los Angeles, CA, with her 2nd husband, Wm Garcia, a 2nd generation Portuguese immigrant born in MA… (Wonder if they come from the Azores Islands???) &amp; a 6 yr old son William. Young William also shows up on the 1940 census, when his mother has now married to her 3rd husband Henry Thoss… Now to tackle the Thoss side of the census records…
    Can’t wait until the 1950 census is released in 2022, so we can follow up on more enticing threads throughout our family lines!!