both would be from Kenninghall, Norfolk.
I think they are brothers.
This is what I have on James Revett:
James Revett: b 1806, Kenninghall, Norfolk. Father was James Rivett b.1778, Kenninghall. Mother was Abilgail Knight b.abt 1778, in Kenninghall. Information verified by an old family history entry. The name changed its spelling to Revett when James apparantly emmigrated to America about 1824. His children were American born: Abilgail, Matilda, Elizabeth Jane, James, George, John, Thomas, Joseph, Mineva...all Revetts by now. His wife was Sarah Haskins/1815 in New York or Pennsylvania.
This is what I have on John Rivett. Born 1813, Kenninghall, Norfolk. Married first to a Susan Nash/1812, then to a Frances/Fanny Hudson (Machin)/b1829 in Holme Hale. Children: Sarah Ann/1837, Elizabeth/1839, John/1845, James/1847, Thomas/1850, Robert/1852...then, Susanah/1857, Mary Jane/1859, Elizabeth/1862.
Looking to try to link these two up using the 41 or 51 census, and whatever sources available. Would like to confirm this somehow or another.
Thanks
Mike