There is no easy way to find the name of the slave she owned as listed on the 1850 Slave Schedule.
He either became a free person in 1863 with the Emancipation Proclamation or she sold him before then.
Purchase and sale of slaves were sometimes recorded in with the land/deed records and court records. I doubt the record would have been in Jemima's name since she was a woman. It would have been in her father or husband's name.
I think she married William Cleowam.
Born: 20 Feb 1859, Clinton Co. KY
F: James Cleowam
M: Jemima Ann Ferguson
Source: KY Births & Christenings 1839-1960
I'd contact the Clinton County Historical Society
Albany 42602 and ask if they have slave records, court and deed records.
If not, I'd contact the Kentucky Historical Society, www.history.ky.gov/research-services/
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