About Mary Sibbet Copley
Mary Sibbet Copley Thaw (June 19, 1843 – June 9, 1929) was an American philanthropist and charity worker. == Early life == Mary was born at Appleby Manor near Kittanning, Pennsylvania in Armstrong County on June 19, 1843. She was the daughter of Margaret and Josiah Copley, a pioneer editor who was well known in the community. == Personal life == In 1867, she married William Thaw, Sr. (1818–1889) after the death of his first wife. Together, they had five children that survived childhood: Harry Kendall Thaw (1871–1947), who would later murder Stanford White In his will, he left $10,000, less than 1% of his fortune, to wife Evelyn Nesbit. Edward Thaw (1873–1924), who married Jane Olmsted (1880–1958) Josiah Copley Thaw (1874–1944), who married Mary Harrington Thomson (1881–1947) Margaret Copley Thaw (1877–1942), who first married George Lauder Carnegie (1876–1921), nephew of Andrew Carnegie. After his death, she married Roger, Comte de Périgny and became Countess de Périgny. Alice Cornelia Thaw (1880–1955), who married George Seymour, 7th Marquess of Hertford (1871–1940). They divorced and she married Geoffrey George Whitney, Sr.
Biography source: Wikipedia. The profile adds birthday-specific historical context from the Celebs Birthday Today editorial database.