I don't have anything on John Flowers, but I have William Duncan's father as Edmund Dunkan, Sr.(my 5th great-grandfather).His will is transcribed at this web address:
This is the information I have on Edmund Dunkan, Sr.:
Descendants of Edmund Dunkan, Sr.
Generation No. 1
1.EDMUND1 DUNKAN, SR. was born Abt. 1730 in Ulster, Ireland, and died Bef. October 1799 in Duplin Co., NC.He married GRACE LNU Abt. 1759 in Craven Co., NC.She was born Abt. 1735 in Duplin Co., NC, and died Abt. 1800 in Duplin Co., NC.
Notes for EDMUND DUNKAN, SR.:
The Dunkans from Ulster, Ireland, were apparently among the first Scotch-Irish settlers in North Carolina:
"The first actual settlement of the Scotch-Irish in North Carolina was not in the Piedmont, but in the Tidewater region; and they arrived by sea rather than by way of Pennsylvania. On November 29, 1735, Governor Johnston informed his Council that Arthur Dobbs (later to become governor of the provice), 'and some other gentlemen of distinction in Ireland,' and Mr. Henry McCulloch, a merchant of London (later agent for Lord Granville) had written him 'respecting their intention of sending over to this province several poor Protestant families with design of raising flax and hemp.' They asked for a grant of 60,000 acres of land in New Hanover County. Their request was granted and in the next year (1736) the settlers arrived at their land on the Black River (now Duplin County), where they organized themselves into two congregations, Goshen and the Grove."(Colonial Records of North Carolina, Vol IV pg 72-73)
1790 Census for Duplin Co., NC shows:
DUNCAN EdmundDuplin 2 3
DUNCAN EdmundDuplin 1 1 2 1
DUNCAN IsaacDuplin 1 2 3
DUNCAN IsaacDuplin 1 2
DUNCAN JosephNew Hanover 2
DUNCAN WilliamDuplin 2 4 4 3
More About EDMUND DUNKAN and GRACE LNU:
Marriage: Abt. 1759, Craven Co., NC
Children of EDMUND DUNKAN and GRACE LNU are:
2. i. WILLIAM2 DUNCAN, b. July 7, 1755, Duplin Co., NC; d. Bef. October 20, 1806, Duplin Co., NC.
ii. ISAAC DUNKAN, b. 1758.
iii. EDMUND DUNKAN, b. 1760.
iv. ANNA DUNKAN, b. 1762.
v. SARAH DUNKAN, b. 1764.
vi. MARY DUNKAN, b. 1766.
vii. GRACE DUNKAN, b. 1768.
viii. GEORGE DUNKAN, b. 1770.
ix. CATRON DUNKAN, b. 1772.
Generation No. 2
2.WILLIAM2 DUNCAN (EDMUND1 DUNKAN, SR.) was born July 7, 1755 in Duplin Co., NC, and died Bef. October 20, 1806 in Duplin Co., NC.He married ANNE CIVIL KORNEGAY August 2, 1778 in Duplin Co., NC1, daughter of JACOB KORNEGAY and MARY FONTAINE.She was born Abt. 1759 in Craven Co., NC, and died Abt. 1839 in Duplin Co., NC.
More About WILLIAM DUNCAN and ANNE KORNEGAY:
Marriage: August 2, 1778, Duplin Co., NC1
Children of WILLIAM DUNCAN and ANNE KORNEGAY are:
i. EDMUND3 DUNCAN, b. 1779, Duplin Co., NC.
ii. JACOB DUNCAN, b. 1780, Duplin Co., NC.
iii. ELIZABETH DUNCAN, b. 1781, Duplin Co., NC.
iv. WILLIAM DUNCAN, JR., b. 1783, Duplin Co., NC.
v. ISAAC DUNCAN, b. 1785, Duplin Co., NC.
vi. ROXALINE DUNCAN, b. 1786, Duplin Co., NC.
vii. STEPHEN F. DUNCAN, b. 1786, Duplin Co., NC.
viii. CATHERINE DUNCAN, b. 1789, Duplin Co., NC.
ix. LEWIS DUNCAN, b. 1790, Duplin Co., NC.
x. JOSEPH DUNCAN, b. 1792, Duplin Co., NC.
xi. ANNE DUNCAN, b. 1799, Duplin Co., NC.
3. xii. SARAH DUNCAN, b. May 18, 1796, Sampson Co., NC; d. Abt. 1842, Sampson Co., NC.
xiii. JOHN CHARLES DUNCAN, b. 1803, Duplin Co., NC.
Generation No. 3
3.SARAH3 DUNCAN (WILLIAM2, EDMUND1 DUNKAN, SR.) was born May 18, 1796 in Sampson Co., NC, and died Abt. 1842 in Sampson Co., NC2.She married ELIJAH GREGORY, son of LOTT GREGORY and NANCY.He was born July 13, 1786 in Sampson Co., NC3, and died December 15, 1843 in Sampson Co., NC.
Notes for ELIJAH GREGORY:
Elijah and Elisha were twins.
Children of SARAH DUNCAN and ELIJAH GREGORY are:
i. MARIAH WILLIAMSON4 GREGORY, b. February 21, 1813; d. Unknown.
4. ii. WILLIAM S. GREGORY, b. April 25, 1815; d. Unknown.
iii. ELIZA ANN GREGORY, b. August 20, 1817; d. Unknown.
iv. LOUIS GREGORY, b. August 26, 1818; d. Unknown.
5. v. MARSHALL HOOKS GREGORY, b. October 12, 1822, Sampson Co., NC; d. January 5, 1898, Attala Co., MS.
vi. ELANY GREGORY, b. September 3, 1824; d. Unknown.
Notes for ELANY GREGORY:
Elany's twin died at birth.
vii. SALLY JANE GREGORY, b. October 15, 1827; d. Unknown.
viii. NANCY GREGORY, b. July 30, 1829; d. Unknown.
ix. ELIJAH JAMES GREGORY, b. January 10, 1831, Sampson Co., NC; d. Unknown; m. MARTHA ANN CHESNUTT; b. Abt. 1837, Sampson Co., NC; d. , Barbour, AL4.
x. JOHN THOMAS GREGORY, b. July 17, 1833; d. Unknown.
Notes for JOHN THOMAS GREGORY:
An 1870 census of Sampton Co., NC shows "Monks Store, Westbrook Township:hesnutt, Adolphus, 27 w m farm" living with John T. Gregory.
xi. HENRY GREGORY, b. January 7, 1836; d. Unknown.
xii. HUBERT FRANCIS GREGORY, b. January 3, 1838; d. Unknown; m. ANNA JANE RICH.
xiii. ELIZABETH GREGORY, b. May 6, 1841; d. Unknown.
Hope this helps.