Samuel Campbell and Mrs. Sarah Foster Coulter.
Samuel Campbell was born circa 1761 in Cecil County, Maryland. I'm not sure who his parents were at this point in time so I'm not going to venture a guess.  Sarah Foster was twice married first to Samuel Coulter November 18, 1778, in Cecil County, Maryland, 1 and then Sarah Coulter was married to Samuel Campbell on November 9, 1786. 2  Samuel has been proven to Gallia County, Ohio as early as 1815.

According to Sarah's gravestone, which was included in the book Cemeteries of Green Township, Gallia County, Ohio. 3 Her stone was read on May 30, 1976. Sadly in a little over 30 years the sandstone is so badly deteriorated that little remains to be read, but in 1976 it was recorded that she buried at Hulbert Cemetery, and she died March 12, 1834, 73 years of age. Making her date of birth approximately 1760 (making her 18 when she first married).  Here is her gravestone in 2007. I've seen it suggested that her father was James Foster who was born in Gilnahirk, County Down, Ireland on January 16, 1762, but that's not possible seeing that he would have only been 1 year old at the time of her birth.

Following his death (March 7, 1841 4) his son Elisha sued his siblings for breach of promise for caring for their father. In this case he names all Samuel's children and lists the children of Samuel's deceased children.  Samuel's children are listed as:
1. Elisha (the plaintiff in this case)  The following children are from his will which was dated February 19, 1845. 5 d. April 20, 1845 6
a. Samuel (after he reaches 21, so he was born after 1824)
b. Margaret
c. Elizabeth C
d. Sarah C
e. Nancy C
f. Lydia
2. Nancy Campbell Graham, the wife of James Graham of Gallia County. d. June 16, 1846 (49 years old) 7
a. Mary E. Graham wife of Hamilton Willis (of Wayne County, WV)
b. James M. Graham (of Gallia County)
c. William Graham (of Gallia County)
d. Charles W. Graham (of Lawrence County, Ohio)
e. Lorenzo D. Graham (deceased)
3. John Campbell of Illinois
Will take some sleuthing to find.
4. Elijah Campbell of Gallia Countyd. between the 1850 and 1860 census
a. unknown female (from 1830 and 40 census)
b. Thomas S
c. Samuel
d. Martha
e. Alonzo
f. James
g. Mary
5. James Campbell, deceased (his children are listed as follows, all living in Indiana): d. prior to Oct. 17, 1842
a. Rachel, wife of Alexander Waddell
b. John
c. Sarah
d. Margarite wife of [blank] Young
e. Nancy wife of [blank] Shoemaker
f. Samuel
g. William
h. Jane (minor as of Oct. 17, 1842)
i. Mary (minor as of Oct. 17, 1842)
j. Elijah (minor as of Oct. 17, 1842)
6. Margaret Campbell wife of John Rees. Margaret was deceased. Her children all living in Gallia County. d. prior to Oct. 17, 1842
a. David Rees
b. Andrew Rees
c. Grizzy Rees (Grizzell L on gravestone b. 1820)
d. Sarah Rees (minor as of Oct. 17, 1842) b. 1823 gravestone
e. Campbell Rees (minor as of Oct. 17, 1842) b. 1825 gravestone
7. Samuel Campbell (deceased) d. prior to Oct. 17, 1842
a. James
b. Mary wife of William Watts
c. William
d. Samuel
e. Sarah
f. Andrew
g. Margaret
Footnotes

1. Maryland Marriages, 1667-1899 on ancestry.com
2. ditto
3. Cemeteries of Green Township, Gallia County, Ohio. Gallia County Historical Society updated July 2002.
4. Gallia County Clerk of Courts Chancery Records Vol 2 1841-1846 Oct. Term, 1842 p. 132-135)
5. Will of Elisha Campbell, dated February 19, 1845.
6. Gallia County Cemeteries Gallia County Genealogical Society, OGS chapter "C"
7. Gallia County Cemeteries Gallia County Genealogical Society, OGS chapter "G"
8. Elijah's children based off 1830, 40 and 50 census.