Hi,
Yes, that is strange. I am only passing on information given to me by the grand daughter of said Sarah, so haven't seen a birth cert. In 1841, after Thomas had died (1831) his wife and daughter were indeed living at Bell Mont farm, Knaresborough so perhaps there is an error somewhere. I will go back to the lady trying to find this information and let her know what you have turned up.
Many thanks,
OzzieJoan