Their son George W Parker died Feb 6, 1908 aged 79 in Chelsea, MA[5]
From his death record we learn that Josiah was born in Dracut, Mass and Martha in Kittery Maine.
Looking at Dracut Vital Records we find:
Birth: Josiah Coburn, s. Daniel and Abigail, Dec. 16, 1797.
Marriage: Daniel and Nabby Coburn, int. June 19, 1797. [m. July 12. CR1].
"United States Census, 1850," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M6V3-GNX : 4 April 2020), Charlotte A Littlefield in household of James Littlefield, Bangor, Penobscot, Maine, United States; citing family 1920, NARA microfilm publication M432 (Washington, D.C.: National Archives and Records Administration, n.d.).
"United States Census, 1860", database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MDC7-95K : 18 March 2020), Charlotte Littlefield in entry for James Littlefield, 1860.
"United States Census, 1870", database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:M669-FW4 : 19 March 2020), Charlotte Littlefield in entry for James Littlefield, 1870.
"United States Census, 1880," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:MHXT-Y9G : 14 August 2017), Charlotte A Littlefield in household of James Littlefield, Boston, Suffolk, Massachusetts, United States; citing enumeration district ED 755, sheet 270D, NARA microfilm publication T9 (Washington, D.C.: National Archives and Records Administration, n.d.), FHL microfilm 1,254,560.