Mary [b. 1858] and Alice [b. 1851] Cassidy were born in County Cavan, Ireland. Their parents were Andrew Cassidy and Alice McDonald. Andrew and Alice had two other children: Biddy [b. 2 July 1865] and Maurice [b. 1869]. Mary and Alice came to New York in the early 1880's. I have a Alice and Mary cassidy arriving on the Archoria on 12 July 1882; I do not know if it is our Mary and Alice Cassidy. We have conflicting dates of arrival and ages for Mary and Alice in the censuses and death certificates.
Mary never marries and works as a domestic. She dies January 1910 in the home of her sister, Alice, at 270 Hudson street, Manhattan. Alice marries Jeremiah O'Keefe about 1891. They have three children: Bernard [b. Mar. 1895], Jeremiah [b. Oct. 1899] and Mary [b. May 1893]. Jeremiah dies 26 June 1918 and Alice dies 2 March 1935. All three are buried in Calvary Cemetary.
Mary O'Keefe2 [Jeremiah1] marries Harry McCrossen about 1917. Harry is policeman in New York City. By 1920 Harry and Mary are living at 646 Halsey St. Brooklyn; Alice Cassidy O'Keefe has moved in with them.
Mary and Harry have three children in 1930: Unlisted [b. 1918], Unlisted [b. 1920] and Unlisted [b. 1923].