Researcher Denise Bunker states that her research shows Irwin Barnum, son of Wheeler Barnum and Catherine Harshman and brother of Wentworth Barnum (her great grandfather), died a single man. She has his death certificate and also found him in the Minnesota Federal Census for 1860, 1870, 1880, 1900, 1910, all stating that he was single. She also found an Irwin Barnum in the Michigan Federal Census for 1870 in Ash, Monroe, Michigan, listed together with William Barnum, a farm labourer. The Head of Household was (illegible) Barnes and wife Charity. An Irwin Barnum is also found in the 1880 Federal Census in Ash, Monroe, Michigan, listed under his brother in-law; John F. (illegible). Albert W. Barnum, listed as Irwin's son here, appears in the 1930 Federal Census for River Rouge, Wayne, Michigan, with a wife named Edith. It appears that the wife and children assigned here to Irwin belong to another person (perhaps named Irwin) who has not yet been identified.