Allen, unfortunatelly, I do not know how he fits in the scheme of things. Here is what I have (attachment), additions / corrections appreciated, thanks, Jim.
I have also been searching for quite some time for the same information: Who are the parents of John J Hagerman (born Nov. 1799, Seneca Co). I believe they are William Hagerman and Sarah Silvernail Jones. I believe that John J. may have been the eldest son. John J Hagerman and Sarah Terry moved to Michigan around 1838 or 1839. William Hagerman died 1835 while Sarah Jones Hagerman died around 1838. Many of the families from Seneca County NY (around Lodi, Ovid, Covert) moved to Lenawee County Michigan around 1832 thru 1838.
I am descended from Joseph W (william?) Hagerman and Betsy Skinner. (also John Clark Hagerman and Clara Rothfuss).