— born in GA, probably in either Butts Co., GA, or Marion Co., GA:
4.  Benjamin Franklin STEWART, b. 1841/2
5.  Eliza J. STEWART, b. 1843/4
6.  Richard Andrew Jackson "Jack" STEWART, b. 1845/6

1.  D.L. Murray & N.R. Murray.  1995.  Marriage Index: AL, GA, SC, 1641-1944.  Salt Lake City, UT (Broderbund CD-3):

Stewart, Richard M

Gray, Isabella

13 Jan 1848

Crawford Co., GA

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

Richard M. STEWART Death:  26 Nov 1850 Marriage: About 1833, of Georgia Spouse: Isabella Source: patron submission

Richard Madison STEWART Birth: About 1808, Marion, Georgia; Death: 14 Dec 1851 Marriage: 13 Jan 1848, Crawford, Georgia Spouse: Isabella CORBIN Birth: About 1823, Georgia Source: patron submission

Several dates are obviously wildly incorrect guesses.  His will was recorded 14 Jan 1851, so the 14 Dec 1851 death date cannot be correct.  A reliable source gives his death date as 14 Dec 1850.

3.  1840 Census Index/Images (online at Ancestry.com, Image #13-14 of 38; extracted by Diana Gale Matthiesen):

1840

GA

Butts Co.

612 Dist.

Roll 37

pp. 174B-175A

Ln. 26

R M Steward

110 011 - 100 001

[no slaves or free colored]

9

0400000

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 male	4 or under	1835-1840	= Thomas (b. 1835/6)
1 male	5-9	1830-1835	= William (b. 1834)
1 male	20-29	1810-1820	= ?
1 male	30-39	1800-1810	= Richard (b. 1807/8)
1 female	4 or under	1835-1840	= Mary (b. 1839/40)
1 female	30-39	1800-1810	= Elizbeth
4	person employed in agriculture

The location makes me wonder if this is our subject, but I can find no one else whose's even a remote fit, and this household fits perfectly.  The numerical data don't jibe with the total number (9) or with the number of persons employed (4).  Adjacent households don't jibe either.  It's not the case that the number pages precede the name pages, because the numbers on the previous page don't jibe, either; nor do the page numbers suggest there are images missing.  I have no explanation beyond that the enumerator didn't know what he was doing.

4.  1850 Census Every-Name-Index/Images (online at Ancestry.com, Image #__-28 of 29 — the first image is missing at Ancestry.com, I had to pull it from Genealogy.com):  Division 57, Marion Co., GA, Roll M432_77 (Book 1), pp. 248A-248B, 308/308, enumerated 17 Sep 185, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):¤•

R M Stewart	42	M		Farmer	20,000	Ga
Isabella "	42	F				SC
Wm W     "	16	M		Student		Ga
Thomas J "	14	M				"
Mary E   "	10	F				"
Benj F   "	8	M				"
[next page]
Eliza J Stewart	6	F				Ga
Richard A J "	4	M				"
Ella Hariet Gray	6	F				"

All of the STEWART children are Richard's from his prior marriage; Ella is Isabella's child from her prior marriage.

5.  Rena S. Cobb.  c1997.  A History of Marion County, Georgia: Motherland of Many.  Wolfe Pub., Fernandina Beach, FL (extract online in the ftp archives of USGenWeb; contributed by Carla Miles):

p. 558

Appendix B: Marion County Wills, Will Book A, 1846-1914... RICHARD M. STEWART - Wife Isabella Stewart; six children: William Washington Stewart, Thomas J. Stewart, M.E. Stewart, B.F. Stewart, I1 L. Stewart, and R.A.J. Stewart.  Witnesses: James Crittenden, L.I. Kilncrase and Thomas H. Stewart.  Other relatives mentioned in will include a brother, James Stewart, cousin, Thomas H. Stewart; cousin W.D. Stewart; cousin Wm. R. Stewart; all named executors.  Daughter Mary E. Stewart and Mary Baivens (Bivins?), sisters were mentioned as heirs also.  Will probated: January 14, 1851.

There seems to be some kind of typo with Eliza J. STEWART's given name, but what we can tell from this will abstract is that Richard & Isabella had no children together, which is not at all surprising given her age when they married.

6.  WorldConnect / Ancestry World Trees (online at RootsWeb.com/Ancestry.com).

7.  Genealogy shared by descendant.  This source (quite reliable), has 14 Dec 1850 as his death date.