Leslie is listed with the family on the 1850 census at Gouvenour, Saint Lawrence County in NY. He next appears on the 1870 census in Union twp, Fulton County, IL (single, 25 yrs old, born NY). The Illinois Marriages 1851-1900 data base on Ancestry: Leslie W. Barnum married Celestia L. Bliss on 14 September 1871 in Fulton County. The next time Leslie appears is in the 1910 census, living with Albert and Evelyn at Rushville, NE. Leslie was listed as "father," 63 yrs old, widower and born in NY.
1870 Census, Union, Fulton County, Illinois, Page 253a, Household 201-198: Austin, Elwell E., 71 (head); Barnum, Leslie W., 25, farm laborer, $600, New York.
From the Rushville Recorder, February 4, 1915 - L.W. Barnum died last Wed night. Funeral will be held tomorrow at the home.