Meredith, haven't we discussed this before? Nancy Wilson Hendrickson is also my ancestor. There are many court documents in Lewis County listing Nancy as an heir of John, along with the Hendrickson children and her two surviving children by John Longley, Nancy and Francis. (The name is sometimes spelled "Langly" or "Longly.")
There was an ongoing, unending, often acrimonious lawsuit against John Wilson's heirs having to do with a land dispute. Some of the entries list "Nancy Longley, dec'd," some do not mention her by name but list her children, or some of her children, etc. Here is one from the Lewis County Circuit Court dated March 1837: "This day came the complainant (Israel B. Donaldson) by his counsel; and the defendants, John Wilson, Moses Gooding, Nancy his wife, John G. Wilson, William Herbert, and Nancy his wife, Samuel Wilson, Joanna Wilson, Ralph Wilson, Henly Wilson, Jennett Wilson, Clark Swadgrass, Thomas Wilson, Cynthia Wilson, Sarah E. Hendrickson, Norman Hendrickson, Francis Langly, Nancy Langly, Amos Evans, and Elizabeth his wife, Andrew Wilson, Ralph Wilson, senior and the unknown heirs of JOHN WILSON, Jr., deceased, and the unknown heirs of ROBERT WILSON ..."
For me, the persistent mention of Nancy and/or her children in these court documents is enough evidence that she was indeed a daughter of John Wilson.