Sarah is said to be born in 1760, but that birthdate cannot be right if Abraham & Rachel are her paretns because Abraham & Rachel weren't married until 1766.  Also, the 1850 census shows Sarah was born 1769/70 and other censuses support that date. 

— born in...
  4.  Elizabeth MARSH, b. 1798; m. David BARTON
  5.  Adam MARSH, b. ca. 1800
  6.  Sarah Ann MARSH, b. 1802; m. 26 Mar 1827, Harrison Co., KY, Joshua EVANS

— born in Bourbon Co., KY:
  7.  Harrison Corbin MARSH, b. 29 Mar 1805; d. 5 May 1889, Dallas Co., TX
  8.  Louisiana J. MARSH, b. ca. 1806
  9.  Nathaniel Corbin MARSH, b. 22 Apr 1808 
10.  Abraham Corbin MARSH, b. 10 Jul 1810; d. 28 Jan 1891, Harrison Co., KY; m. 8 Mar 1832, Mary SMITH (17 Feb 1817 - 22 Jun 1876)

Some secondary sources show our subject with daughter Dryden (MARSH) WOOD, wife of Nimrod WOOD, but she was the daughter of our subject's brother, Beale MARSH.

1.  Marriage Record:

2.  1790

3.  1800

4.  1810 Census Index/Images (online at Ancestry.com; Image #5 of 15; extracted by Diana Gale Matthiesen):

1810

KY

Nicholas Co.

Roll M252_8

p. 427

Ln. 18

Marsh Thos

40011-22210-08

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
4 males	9 or under	1800-1810	= Abraham (b. 1810) = Nathan (b. 1808) = Harrison (b. 1805)  = Adam (b. ca. 1800)
1 male	26-44	1765-1784	=
1 male	45 or over	in or bef. 1765	= Thomas (b. 1753)
2 females	9 or under	1800-1810	= Louisiana (b. ca. 1806)  = Sarah (b. 1802)
2 females	10-15	1794-1800	= Elizabeth (b. 1798) = ?
2 females	16-25	1784-1794	= Sophia (b. 1793) = Rachel (b. 1791)
1 female	26-44	1765-1784	= Sarah
8 slaves	all ages	in or bef. 1810	=

5.  1820 Census Index/Images (online at Ancestry.com; Image #7 of 25; extracted by Diana Gale Matthiesen — part of the record was obscured with tape):

1820

KY

Bourbon Co.

North Middletown

Roll M33_18

p. 86-87

Ln. 32

Thos Marsh

030001-01201-?-???

1100-2000

These data indicate:

No., Race, Gender	Age Class	Therefore Born	Individuals Inferred
3 white males	10-15	1804-1810	= Abraham (b. 1810) = Nathan (b. 1808) = Harrison (b. 1805)
1 white male	45 or over	in or bef. 1775	= Thomas (b. 1753)
1 white female	10-15	1804-1810	= Louisiana (b. ca. 1806)
2 white females	16-25	1794-1804	= Sarah (b. 1802) = Elizabeth (b. 1798)
1 white female	45 or over	in or bef. 1775	= Sarah (b. 1765-70)
1 male slave	13 and under	1806-1820	= ?
1 male slave	14-25	1794-1806	= ?
2 female slaves	13 and under	1806-1820	= ?

6.  1830 Census Index/Images (online at Ancestry.com; Image #11 of 20; extracted by Diana Gale Matthiesen):

1830

KY

Harrison Co.

Easter Division

Roll M19_37

p. 194

Ln. 21

Thomas Marsh

000 020 000 100 - 000 000 001

020000-020000

These data indicate:

No., Race, Gender	Age Class	Therefore Born	Individuals Inferred
2 white males	20-29	1800-1810	= ? = ?
1 white male	70-79	1750-1760	= Thomas (b. 1753)
1 white female	60-69	1760-1770	= Sarah (b. 1765-70)
2 male slaves	10-23	1806-1820	= ? ?
2 female slaves	10-23	1806-1820	= ? ?

Listed 17 lines below Harrison MARSH (æ 20-30).

7.  1840 Census Index/Images (online at Ancestry.com, Image #21-22 of 56 — indexed "March"; extracted by Diana Gale Matthiesen):

1840

KY

Harrison Co.

Cynthiana

Roll M704_113

pp. 155B-156A

Ln. 5

Sarah Marsh

000 - 000 000 000 100

000000-001000

These data indicate:

No. & Sex	Age Class	Therefore Born	Individuals Inferred
1 white female	70-79	1760-1770	= Sarah (b. 1769/70)
1 female slave	24-35	1804-1816	= ?

Listed 15 lines from son, Nathaniel MARSH, who is next to son, Abraham CORBIN.

8.  1850 Census Every-Name-Index/Images (online at Ancestry.com; Image #67 of 133 — indexed "March"):  District No. 1, Harrison Co., KY, p. 84A, 490/490, enumerated 24 Aug 1850, official enumeration date 1 Jun 1850 (extracted by Diana Gale Matthiesen):

Sarah Marsh

80

F

300

Pa

Listed next to her widowed daughter, Sarah (MARSH) EVANS (æ 48).

9.  St. James Parish Register, Maryland, 1787-1815 (online at Ancestry.com):

MARSH CHARLOTTE, bn. to Thomas and Sarah, 7/17/1789

MARSH RACHEL, b. to Thomas and Sarah, 8/20/1791

MARSH SOPHIA, b. to Thomas and Sarah, 9/21/1793

10.  Robert W. Barnes.  1989.  Baltimore County Families, 1659-1759.  Genealogical Publ. Co., Baltimore, MD (Broderbund CD-195):

p. 135

CORBIN, ABRAHAM (5), s. of Edward (3) and Jane, b. 7 Sept. 1722 in St. Pauls Par., d. c. 1798; prob. the Abraham who m. Rachel Marshall on 4 Dec. 1766; had iss.: ABRAHAM; THOMAS; NICHOLAS, by June 1805 was in Bourbon Co., Ky., when as one of the heirs of Abraham Corbin, dec., he sold pt. The Valley of Jehosophat to Joshua Marsh; NATHAN; SARAH, m. Thomas Marsh, Jr.; ELEANOR, m. Beale Marsh  (131; 133; 231-WG#56:122; 231-WG#86:252).

11.  William Henry Perrin, ed.  1882.  History of Bourbon, Scott, Harrison and Nicholas Counties, Kentucky.  O. L. Baskin & Co., Chicago.

p. 692

NICHOLAS C. MARSH, farmer; P. O. Oddville; was born in Harrison County, Aug. 4, 1833; his grandfather, Thomas Marsh, came from Maryland, near Baltimore, in the latter part of the eighteenth century, and settled in Bourbon County; afterwards moved to Nicholas, thence to Harrison, where he died at the advanced age of eighty-four.  Nathan C. Marsh, father of our subject, was born in Bourbon County, April 22, 1808...

12.  WorldConnect / Ancestry World Trees (online at RootsWeb.com/Ancestry.com).  Has Sarah b. 1760.

13.  Messages in the Marsh Family Genealogy Forum (online at GenForum.com).