The author of that family history apparently loses John after a land transaction in 1799 where he sold his property in Ashby, Massachusetts, and indicated that it was thought that John left the area after that point in time.
And, for unexplained reason, the author indicated that John Gibson died after 10 April 1811. The author makes no reference as to why they knew John was alive on that date. In all honesty, I need to read more completely the Gibson genealogy from which the information on John was obtained to see if there is any other reference to that 1811 date--it may be that he signed or appears in some sort of probate or other estate settlement document. But that's only a guess.
Apparently at some point, some genealogist has taken the "last alive by date" for John and converted it into a death date. That date is given as John's death in numerous online references, all seemingly copied from the initial date converter.
I've not thrown out the online references to John and his children. Just because a compilation has one fact apparently interpreted incorrectly does not mean that other information in those compilations is incorrect. Those compilations have given me solid leads on John's children, specifically:
- Catherine Gibson, born 1783 in Ashby
- John Gibson, born 1778 in Ashby