Phyllis, sorry I can't help on parentage of Amos Knapp. But I do have Ezra Knapp, born 1816 Ohio, m. Martha Jane Godbold, June 23, 1842, in MS. Children: Samuel D. Knapp, b. 1846; J. W. Knapp, b. 1846; Mary E. Knapp, b. 1849, possibly others. Ezra and your Amos seem to have been in Ohio about the same time. Wonder if there is any possible connection between these lines?