Mary Lance
Daughter of Marie Louise Allard Lance Draper and sister of Nancy Lance Dayton and Sophia Lance Dayton. She married Hiram Dayton at Winter Quarters on 24 February 1848 and crossed the plains with him in 1851. In an account written by Mary Elizabeth Stewart which appears in the "Memories" section of her FamilySearch record, she states that her mother and two of her mother's sisters, all wives of Hiram Dayton, came to Utah with him in 1851.
In the 1856 Utah census she may be one of the two woman named Mary Lance at Lake City (modern American Fork), Utah County. The above birth date is from FamilyTree. The Find A Grave website gives 9 December 1820 as her birth date. Her death date is identical in both sources.