In the 1850 US Census for Lowville, Lewis County, New York the family of Thaddeus Barnum was enumerated as follows:
Dwelling #1070; Family #1076
Thaddeus Barnum, 45, M, Farmer, Real property $2,000, b. New York
Lydia Barnum, 37, F, b. New York
Francis Barnum, 16, M, Farmer, b. New York, Attended school within the year
Eugene Barnum, 1, M, b. New York
Mary Hough, 18, F, b. New York
Mahala Fault, 60, F, b. New York