Aha. In the online Internet Archive I have found a book
History, Town of Isle La Motte, Vermont : An Account of the Discovery, Settlement, and Interesting and Remarkable Events in which it is stated that "Henry Naylor (1820-1898) came from England when he was five years old."
The book was published by A.L. Stratton, North Hero, VT, in 1984. Online access is restricted but I currently have it borrowed from Internet Archive for another 13 days.
I have been working through as comprehensive a list of Henry Naylor/Naylers b 1804-1824 in Yorkshire as I could come up with, using FamSearch, Ancestry and FMP. Of course I started from the 1804 end, didn't I. Merry, I may need you to patiently explain once more the part about "birth registrations of their children to pick up the mmn and then the correct marriage, with (hopefully!) father's name recorded". Oh, never mind, I get it. Or do I?
This will tell me what children to look for on the census? And what else?
