The book titled Tombstone Inscriptions Berwick Township Warren County Illinois, published by the Warren County Illinois Genealogical Society, reports the following burials at Berwick Cemetery, Section C: John Riggs died May 10, 1883 age 84y 2m 25d. Martha A. Riggs died May 28 1860 age 60 2m 14d wife of John Riggs.
Reuben Riggs died Sept. 20, 1848 age 79y 6m 11d. Catherine Riggs died Nov. 23 1855 age 75y 9m 1d wife of Reuben Riggs.
Distantly related by marriage & just trying to be helpful.