Question: Which country Tad Lincoln's mother is from?

Knowledge 1: Tad Lincoln
Thomas "Tad" Lincoln III (April 4, 1853 – July 15, 1871) was the fourth and youngest son of Abraham and Mary Todd Lincoln.The nickname "Tad" was given to him by his father, who observed that he had a large head and was "as wiggly as a tadpole" when he was a baby.Lincoln was known to be impulsive and unrestrained, and he did not attend school during his father's lifetime.He had free run of the White House, and there are stories of him interrupting presidential meetings, collecting animals, and charging visitors to see his father.He died at the age of 18 on July 15, 1871, in Chicago. [SEP] Knowledge 2: Mary Todd Lincoln
Mary Todd Lincoln (Mary Ann Todd; December 13, 1818 – July 16, 1882) was the wife of the 16th President of the United States, Abraham Lincoln, and as such the First Lady of the United States from 1861 to 1865.She dropped the name Ann after her younger sister, Ann Todd (Clark), was born, and did not use the name Todd after marrying.Mary was a member of a large, wealthy Kentucky family, and was well educated.After finishing school during her teens, she moved to Springfield, Illinois, where she lived with her married sister Elizabeth Edwards.Before she married Abraham Lincoln, Mary was courted by his long-time political opponent Stephen A. Douglas.She and Lincoln had four sons together, only one of whom outlived her.Their home of about 17 years still stands at Eighth and Jackson Streets in Springfield, Illinois.She supported her husband throughout his presidency.She witnessed his fatal shooting when they were together in the President's Box at Ford's Theatre on Tenth Street in Washington.Mary was briefly involuntarily institutionalized for psychiatric disease ten years after her husband's assassination, but later retired to the home of her sister.She also complained of many physical symptoms during her adult life.
Knowledge 1: Mary Todd Lincoln
Mary Todd Lincoln (Mary Ann Todd; December 13, 1818 – July 16, 1882) was the wife of the 16th President of the United States, Abraham Lincoln, and as such the First Lady of the United States from 1861 to 1865.She dropped the name Ann after her younger sister, Ann Todd (Clark), was born, and did not use the name Todd after marrying.Mary was a member of a large, wealthy Kentucky family, and was well educated.After finishing school during her teens, she moved to Springfield, Illinois, where she lived with her married sister Elizabeth Edwards.Before she married Abraham Lincoln, Mary was courted by his long-time political opponent Stephen A. Douglas.She and Lincoln had four sons together, only one of whom outlived her.Their home of about 17 years still stands at Eighth and Jackson Streets in Springfield, Illinois.She supported her husband throughout his presidency.She witnessed his fatal shooting when they were together in the President's Box at Ford's Theatre on Tenth Street in Washington.Mary was briefly involuntarily institutionalized for psychiatric disease ten years after her husband's assassination, but later retired to the home of her sister.She also complained of many physical symptoms during her adult life. [SEP] Knowledge 2: Julia Taft Bayne
Julia Taft Bayne (March 4, 1845 – December 14, 1933) was an American author who wrote a memoir of the Lincoln White House entitled "Tad Lincoln's Father" (1931), based on her time visiting the household as a teenager with her younger brothers.
Knowledge 1: Tad Lincoln
Thomas "Tad" Lincoln III (April 4, 1853 – July 15, 1871) was the fourth and youngest son of Abraham and Mary Todd Lincoln.The nickname "Tad" was given to him by his father, who observed that he had a large head and was "as wiggly as a tadpole" when he was a baby.Lincoln was known to be impulsive and unrestrained, and he did not attend school during his father's lifetime.He had free run of the White House, and there are stories of him interrupting presidential meetings, collecting animals, and charging visitors to see his father.He died at the age of 18 on July 15, 1871, in Chicago. [SEP] Knowledge 2: Eleni Gabre-Madhin
Eleni Zaude Gabre- Madhin, an Ethiopian economist with Swiss nationality, is a former Chief Executive Officer of the Ethiopia Commodity Exchange( ECX).She has had many years of experience working on agricultural markets – particularly in Sub- Saharan Africa – and has held senior positions in the World Bank, the International Food Policy Research Institute( Washington), and United Nations( Geneva).

Answer: United States