Seeking family of Samuel William Mather

I am looking for Samuel William Mather's ancestors and family background.  The available story of his life begins in America as an apprentice to Thomas Paschall, a pewterer/silversmith in Philadelphia who emigrated from England.  Mather married Paschall's daughter, Margaret, and they moved to Forks, PA, where they farmed the land.  Margaret Paschall was a Quaker, but Mather wasn't, so their wedding took place at, I think, Christ Church, in Phila..

Mather was born approximately 1716 presumably in the New World and was called by his middle name of William.  I could not find a record of him in the New England Mather line.  The names "Samuel" and "William" have been recycled often within the Mather families.  He died quite young, after only a few years of marriage, so I'd like to know how he died and where he's buried as well as his background and ancestors.