Richard,
Great digging in Lorena's Book.
I have been using it for several years and I missed the Seabaugh connection on page 321 altogether.
Otto, in his book, Suggests that Christopher and Jacob were brothers rather than father and son. He does say that father son is possible. His writing came before Lorena's research and I lean toward her conclusion. The Joseph Nueschwonger who sold Jacob 97A would be a half brother. Makes sense!
Otto has documented Revolutionary War service by Christopher, Christian and Jacob, sighting service records of Pennsylvania militia companies.
By the way, The Eva Katherine Statler who married Joseph Niswonger was my 3rd gr grand aunt. The Christina Statler who later married Christopher Seabaugh was her sister.