I noticed that on the Illinois death certificate for William B Keller that it said he was buried in Johnstown, PA., so I looked on the Johnstown Tribune Obit index. They published an obit for him on 1913-11-13 and 1913-11-14. If you are in that area it would be worth looking them up in the library. If you are some distance away it is probably worth the $5 each to get one or both of them. It looks like his wife- Mary E Keller- has an obit 1903-5-9.
If you get lucky, it will mention surviving siblings.
My big question about the William Davis - age 3 - living in the George Kellar household in 1850 is where does he go in 1860? George and his wife are in the same place, along with their son, Henry. The rest of the children would range in age from 21 to 35, so it makes sense that they are off starting their own families, but William Davis would only be 13 or 14. I'm suspicious that if I could find Elizabeth Kellar, there would be a 13 year old William living with her - who knows what surname the census taker might have attached to him.
I am interested in a copy of George Keller/Kellar's will, since you are willing to share. It sounds like it will help verify some of the girls' married names.
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