1) His parents were NOT William Willett (& Hannah Foster Skinner -- btw, there is no proof that his wife was this woman -- We only know that his wife at the time of his death was "Isabella")
This Cornelius lived in Washington County, NY, is buried there and it is not likely that he ever went west.
2)His parents were NOT Cornelius Willett & Nancy Whallon -- that man also lived in Washington County, NY, is buried there and it is also not likely that he ever went west
You may want to contact Albert J. Willett who has more information on the NJ clan.There was a Cornelius, son of William Willett & Penelope Wyckoff who was born in NJ close to the date you mention.His wife is aid to have been Hannah McKinistry, but there could have been more than one marriage.
I have definite proof of the above Corneliuses, as they are in my allied line.I have lots of documentation.