I am searching for David (Mahlon) Knadler born aprox 1857 Carroll, IL

I have him in the 1860, 1870, and 1880 census' then a marriage in 1882 after that he drops off the face of the earth. I have searched IL death records, Find a grave, newspapers, geneology trail. Buried with any of his siblings. Nada!

Any help would be appreciated.

Below is the link to my tree

http://trees.ancestry.com/tree/34034356/person/20000730114