Jeff, my gr-gr-grandmother was Mary KNISS born (according to her gravestone) 29 December 1818 in (according to the 1850 - 1900 censuses) in Pennsylvania. She married Michael RHODES about 1838 and her first three children were born in PA. In the neighboring Indiana county is an Issac KNISS born 1815 in PA who could be Mary's brother.
In the days of printed census Indices the only KNISS I found in PA was Wright KNISS in Lancaster County. With Ancestry, I see a Samuel and Jacob KNISS in Northumberland County but cannot find Wright KNISS any place.
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