Mary Scott McKee was the acting First Lady of the United States for her father Benjamin Harrison. She lived in the White House for the duration of her father's presidency where she worked as an assistant to her mother, first lady Caroline Harrison. She became the acting first lady after her mother's death in October 1892 and remained in the role for the final months of her father's presidency. McKee's young son, known as Baby Harrison, was a popular national figure during the Harrison administration. She disassociated from her father following his marriage to her young maternal cousin Mary Dimmick.

First Lady of the United States (FLOTUS) is the title held by the hostess of the White House, usually the wife of the president of the United States, concurrent with the president's term in office. Although the first lady's role has never been codified or officially defined, she figures prominently in the political and social life of the United States. Since the early 20th century, the first lady has been assisted by official staff, known as the Office of the First Lady and headquartered in the East Wing of the White House.