Mary Ann McDonald was born on March 14, 1844, in Moore County, North Carolina, to Neill and Margaret McDonald. Her father was a farmer who owned $250 of real estate and $2,000 of personal property by 1860. She grew up and attended school in Moore County. She married William Whitlock on August 18, 1863, and they had at least eleven children: William, born around 1865; Eliza, born around 1866; Neill, born around 1868; James, born around 1870; Margaret, born around 1872; Martha, born around 1874; Reams, born around 1876; Serena, born around 1876; John, born around 1878; Carson, born around 1881; and Benjamin, born around 1884.
They lived in Moore County, and her husband worked as a farmer. By 1870, they owned $500 of real estate and $75 of personal property. Her husband died in 1891. She moved to Rockingham, North Carolina, in the late 1800s, and by 1910, she was living in her son Benjamin’s household in Carthage, North Carolina. She died of old age in Rocky Spring, North Carolina, on July 25, 1915.