1.  Timothy Hopkins.  1932.  John Hopkins of Cambridge, Massachusetts, 1634, and Some of His Descendants.  Stanford Univ. Press, Stanford, CA.

2.  LDS.  Family Search: Internet Genealogy Service:  IGI - International Genealogical Index (online at FamilySearch.org).

Henry Kellogg HOPKINS Spouse: Juliette E. BUELL Marriage: 15 Jun 1831, Bergen, Genesee, New York Source: [patron submission]

3.  Census Index:  U.S. Selected Counties, 1830 (Broderbund CD-315):  cannot find Henry, though there are BUELLs and other HOPKINSes in Bergen, Genessee Co., NY.

4.  1840 Census Index/Images (online at Ancestry.com; Image #53-54 of 68; extracted by Diana Gale Matthiesen):

1840

NY

Niagara Co.

Lockport Village

pp. 92A-92B

Henry K. Hopkins

000 021 - 001 010

0000001

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
2 males	20-29	1810-1820	= Moses (b. 1817) = Mark (b. 1813)
1 male	30-39	1800-1810	= Henry K. (b. 1807)
1 female	10-14	1825-1830	= ?
1 female	20-29	1810-1820	= Juliette (b. 1815)
1	persons engaged in learned professions and engineers

Henry was an attorney, and his brother, Mark, studied law under him, so Mark is undoubtedly one of the younger males.  The other male is probable their younger brother, Moses, who was also not known to be married at this time.  Both of their parents were deceased by 1837, so we do not find the unmarried children in their parents' household.  The younger female is too old to be Henry & Juliette's daughter, and Henry was not known to have had a sister, so perhaps she is kin of Juliette's.

5a.  Census Index:  U.S. Selected Counties, 1850 (Broderbund CD-317):

1850

Hopkins, Juliett

NY

Niagara Co.

Lockport

p. 112

5b.  Family Quest Archives:  New York Federal Census 1850: Niagara County (part).  Heritage Quest CD M432-560:  Lockport, Niagara Co., NY, p. 112B, 1593/1736, enumerated 8 Aug 1850 (extracted by Diana Gale Matthiesen):

Stephen Mariam	65	M	Farmer	2000	NY
Sarah     "	54	F			"
Hariet    "	18	F			"
Juliett Hopkins	35	F			"