Cathy, a bit more details, if you have them, would be helpful in trying to help you. Approximately when was Annie born and approximately when (and where) did she and John marry?
I perhaps located them on the 1901 census of Canada living in Shelburne: Annie age 25, John age 24; Dora age 9. John's occupation shown as ship carpenter. (Ref: Year: 1901; Census Place: Shelburne (Town/Ville), Shelburne & Queens (shelburne), Nova Scotia; Page: 3; Family No: 30).
I found a John D. and Annie E. Tobin on the 1920 US census in Newington, Rockingham, New Hampshire: John age 42 (born Nova Scotia); Annie age 44; children Charles M age 18, George F age 17, Elsie J age 12, Lauretta age 1-3/12. (Ref: Year: 1920; Census Place: Newington, Rockingham, New Hampshire; Roll: T625_1013; Page: 6A; Enumeration District: 124; Image: 932). John's occupation is a bolter in a shipyard, so this seems as if it's them.
I also located a divorce record for John D. and Annie E. Tobin, marriage date 25 Feb 1899, divorce date 13 Feb 1923, in New Hampshire; reason: adultery (Ref: “New Hampshire, Marriage and Divorce Records, 1659–1947.” Online index and digital images. New England Historical Genealogical Society. Citing New Hampshire Bureau of Vital Records, Concord, New Hampshire).
I found a border crossing for their daughter, Elise E. Tobin, from Canada to the U.S. in May 1919, age 11. It shows her grandmother as Esther Blackmore (Ref: The National Archives at Washington, D.C.; Washington, D.C.; Manifests of Passengers Arriving at St. Albans, VT, District through Canadian Pacific and Atlantic Ports, 1895-1954; National Archives Microfilm Publication: M1464; Roll: 369; Record Group Title: Records of the Immigration and Naturalization Service; Record Group Number: 85).
If you happen to be a member of ancestry.com, this is where I located all of this...