The 1850-1880 Censuses record Charles Maurice Tallyrand McCauley (occupation Lawyer), his wife (Henrietta Fitzhenry Dillon) and several children, non of which are Anderson McCauley.
The 1860 Census lists an Anderson McCauley born in 1848 Georgia. His father is listed but no mother. His father's name is difficult to read but it looks like William.
As stoked as I was to have such a great Civil Rights icon in the family (Charles McCauly being a distant cousin) I have to disagree with her cousin's account of family history.