Harriet was the daughter of Biddy Mason. She was an African American woman enslaved by Robert M. Smith, who took her to Utah.
The 1850 Census was actually taken in 1851.
The 1900 Census states that Harriet was born August 1847. John Brown's company of 10, report, 1848 June, states listed Harriet's age as "3/4." No original sources have been located to identify an exact birth date. Indirect and secondary sources state and imply a birth year ranging from 1846-1848.