Ichabod Hovey 1759-1811 and daughter Sylvinia Hovey 1799-1878

Needing proof Sylvinia was Ichabod Hovey daughter for both DAR and Mayflower Society
Ichabod Hovey was in the Revolutionary War and is listed on muster rolls, however no pension for land was filed by him or widow pension for his wife (that I can find). It probably would only be a widow claim as he died in 1811...going over Niagara Falls. The only death info I can find is this newspaper article:
https://mediasvc.ancestry.com/v2/stream/namespaces/1093/media/0410619c-…

Now he is in the Census for 1810, but only head of households names are in that Census. His daughter, Sylvannia Hovey doesn’t show up till she is married so it shows as Sylvannia Amerman in the 1820census. I have some proof of a couple of her brothers and her sister as relatives and living in the same place in New York. So I’m trying to find some proof of Ichabod as their father. However, any of the children born in New York don’t seem to have any proofs of birth. I’ve written and paid Ontario County, NY but they could not find anything. Also “The Hovey Book” has no information on this branch.