The 1860 census (with Daniel age 32) and 1870 census (Daniel age 42) data for Daniel, Caroline, William and Francis is the family in question. Hence Daniel's birth about 1828. However, Caroline's ME birth in census is suspect.
Source for Caroline: familysearch.org, search for Francis Dow, father Daniel, United States: the Francis Asbury Dow record is the Francis in the above 1860 & 1870 census. Here Caroline is born in 1828 in Scotland.
Ergo, do not think Daniel, son of Jeremiah Dow and Phoebe in "The Book of Dow" age 16 in 1850 is same Dow.
Have some, but not sure if complete, "Dow" census index data for York Co., but no details: 1820 (Daniel in Hollis),1830 (Jeremiah in Biddeford 1st Terr), 1840 nothing, 1850 nothing, 1860 (Daniel in Biddeford, Jeremiah in Biddeford). Any help here?