I cannot speak of the document you have but what I have been given of my grandmothers research which she did and had validated by the Mayflower society, is that Daniel Landis Longacre b. 15 apr 1842 in Penn. married on 18 Dec 1872 with Sophia Harbaugh born 27 feb 1850 of Quincy Pa. Sophia died 28 feb 1901 in Elkhart Illinois. and Daniel on 18 apr 1883 near Lincoln Illinois. They had three children, Ellen (1874), Mary (1876-my relation), and Fred (20 Aug 1879).
I see no connection to Canada. Is it possible these similar names are different in dates or location? Please respond as to how this checks with your data. I have nothing on Mary's siblings descendents or marriages. but I have about 5 generations back on the Longacre side and 3 on the Harbaugh.