There is supposed to be a listing for her in 1920 on the same page as her son in Brown Co according to the AIS Census Index that all of the subcription services are using.
According to the data is in NARA Series T625 in microfilm roll 1351 on page 07 sheet A in Enumeration District 32.The problem with Ancestry is that their search engine will put you in District 28 instead which is Franklin Township.
I requested all listings for Hunting Township as well as Huntington Township.Then I requested the Aberdeen Township.The result for all three went to the Franklin Township pages.I have alerted them that they have a problem.
In the meantime, the strange part is that the OhioHistory.org/dindex/ for the years 1913-1937 Death Index shows one Theodocia dying in Summit County OH on 24 OCT 1917 seen in Volume 2408 and Certificate # 67890.If this is the same person she may have been living with one of the children when she died. Perhaps with Irene.
To muddy the water more so we have to deal with several of listings for Theodocia in variable spellings for each of these individuals.In any given census you see Theadocia, Theadosia, Theodocia, Theodosia, and Theodosea.
In the early 1990`s I was following a COOPER line in OH and came upon the Zenas/Zenos listings and saw this Theadocia/Theodocia listings in the census.At the time I did not know the wife`s maiden name.
Anywho, I had a slow day and was catching up on the COOPER posts to see if the was anything that I could add or advise on and saw your posts that jolted my memory about crossing the paths of your COOPER.
Too bad the Brown Co OH page is without a manager at this time.I noticed that OH is great in listing marriages for 1803-1900 but does not itself release death data before 1958.Go figure.
I did notice that Theodosia in each census shows she was born in OH and her father was from KY and her mother was from OH.