Fact: Census (1850) Cape Vincent, Jefferson, New York
"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MCYK-4N1 : 9 November 2014), Eunice Stedman in household of Luther Stedman, Cape Vincent, Jefferson, New York, United States; citing family 534, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).
It may be possible to confirm family relationships with Eunice by comparing test results with other carriers of her ancestors' mitochondrial DNA.
However, there are no known mtDNA test-takers in her direct maternal line.
It is likely that these autosomal DNA test-takers will share DNA with Eunice: