Mary Eunice Harlan
Mary Eunice Harlan was the daughter of United States Senator James Harlan and the wife of Robert T. Lincoln.
The eldest child of James Harlan and Ann Eliza Peck, Mary Eunice Harlan was born in Iowa City, Iowa on September 25, 1846. The only one of James Harlans children to live to adulthood, she was raised in Mount Pleasant, Iowa and Washington, D.C. She was educated in Mount Pleasant and at Madame Smiths Finishing School in Washington. In addition to learning French, dancing and deportment, Mary Harlan received training in music and became an accomplished harpist.
Source: Wikipedia