My marriage record books start from 1867. I can't find a marriage record from Mary Osborn. I don't have any divorce records. You might want to try writing to the Dallas County Historical Society. They might be able to help you.
Dallas County Historical Society, Inc.
P.O. Box 594
Buffalo, MO 65622
I did see some other Osborn's in the cemetery records. Need any other lookups just let me know.
Billy