My gg grandfather, William Rainbow, was also shown in the 1850 NY census. He was married to Henrietta McNull and they had 6 sons: John Edmond, William, Charles (died in infancy), James Henry, George Samuel and Edgar. gg grandfather, William, was suppose to have died in a train accident. Henrietta and children settled in Illinois and later Iowa.
John Edmond is reported not to had children
William had 5: Wilma, George (a bachelor), Margaret Ann (Maggie) Elizabeth and Elsie.
James Henry had l son : William Charles
George Samuel had l son..Earl and 1 daughter..Lula Mae
Edgar had 2sons: Fred and Bruce both batchelors.
Iam a direct decendant of George Samuel's son
There are several William Rainbows as you well know...if you are a link ..I am assuming it would have to be from William's son William
I have extensive research on Henrietta and each son..but am limited to a Marriage in England between William and Margret Waren in England in 1809 ...this is all I have in England. I am willing to share any info that I have that may be helpful to you in your search
Edna Rainbow Hackler
Always "Chasing Rainbows"