Ida McKinley was the first lady of the United States from 1897 to 1901. She was the wife of President William McKinley and was known for her philanthropic work. She was born Ida Saxton in 1847 and married William McKinley in 1871. She was a strong supporter of her husband's political career and was an active participant in his campaigns. Her three-letter answer to the crossword puzzle is 'IDA'.