First Lady of the United States

First Lady of the United States is the unofficial title of the hostess of the White House. Because this position is traditionally filled by the wife of the President of the United States, the title is sometimes taken to apply only to the wife of a sitting President. However, several women have served as First Lady, as when the President was a bachelor or widower, or when the wife of the President was unable to fulfill the duties of the First Lady herself. In these cases, the position has been filled by a female relative or friend of the President.
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