Classification: Query
Surnames:

I think I have found your Alvaretta - (spelling varies widely). See above for the marriage of James W. Smith & Alvaretta Harden.

1850 Census, Trenton, Hancock, Maine,
Samuel Harden, 29, M. Farmer, born Maine
Menda, 27, F, born Maine
David, 7, M, born Maine
Alvaretta, 2, F, born Maine
Almond, 11/12, M, born Maine

At familysearch.org - from extracted records of Bar Harbor, Maine (Trenton was just next door).

Alphrata H. Harden, b. 18 Dec 1847, Bar Harbor,
Father: Samuel Harden
Mother: Malinda H. Hardny
Indexing project: C50371-1

From Marriage Records of Hancock, County, Maine (quoted above), p. 80:

Samuel O. Harden of Trenton & Malinda Jane Salsbury of same, m. 2 July 1843 by John King.