Marguerite / Margaret Sabin / Savin / Seamus

A 2008 PBS documentary found that Angelou's maternal great-grandmother Mary Lee, who had been emancipated after the Civil War, became pregnant by her former white owner, John Savin. Savin forced Lee to sign a false statement accusing another man of being the father of her child. After indicting Savin for forcing Lee to commit perjury, and despite discovering that Savin was the father, a grand jury found him not guilty. Lee was sent to the Clinton County poorhouse in Missouri with her daughter, Marguerite Baxter, who became Angelou's grandmother. Angelou described Lee as "that poor little Black girl, physically and mentally bruised."

Source: http://www.fampeople.com/cat-maya-angelou_8