Mary was born about 1857 in Minnesota Territory. (1900 census) She is the daughter of James Rave. (Marriage Recs.)
According to the 1900 census, they had been married 20 years, making their marriage date 1880; however, their first son was born in 1885, making the year 1884 more likely.
Mary and Edward Logan had five children, none of whom had died prior to 1900:
1900 Federal Census for Perry, Thurston, Nebraska; Page: 7; Enumeration District: 0185; Description: Perry Precinct; FHL microfilm: 1240941. United States of America, Bureau of the Census. Twelfth Census of the United States, 1900. Washington, D.C.: National Archives and Records Administration, 1900. T623, 1854 rolls.