Caveat: this is not my direct line and I have not verified any of the data given below, not even against census records.
Source: A Rockett-Abernathy Genealogy, by Robert Lynn Gatewood, Conway, Arkansas (1969), LDS microfilm # 973015 item 1.
page 51: Richard Rockett Abernethy, b. 11 Oct 1811 Lincoln Co, NC, d. 20 Feb 1873, Pontotoc MS, md. Mary S. Alexander on 13 Feb 1833; issue: Emeline Abernethy, b. 25 Sep 1834 James Abernethy, b. 17 Jul 1836, d. 11 Apr 1865 Harriett Abernethy, b. 9 Feb 1839 Caroline Abernethy, b. 8 May 1843 Ellen Abernethy, b. 25 Apr 1845 Merritt Abernethy, b. 11 Sep 1848 Robert B. Abernethy, b. 27 Feb 1851 Felix Abernethy, md. Mattie Ware, dau Dr James Ware
page 99: Harriett Abernethy, b. 9 Feb 1839, d. 5 Aug 1860, md Joe Johnson, issue: Leila Johnson md. Robert Barnett Maddie Johnson md. a Mr Servell Richard Johnson
Caroline Abernethy, b. 8 May 1843, d. 12 Jun 1906, md. a Mr Eubanks.
page 100 [missing]
page 101: Robert B. Abernethy, b. 27 Feb 1851, d. 13 May 1920, md. Eliza Rutledge; issue: Ed Abernethy, a doctor, Algoma, MS Will Abernethy, never married Jack Abernethy Mamie Abernethy, md. a Mr Harris Betty Abernethy, md. a Mr Harris Viola Abernethy, md. a Mr Harris Inez Abernethy, md. a Mr Mayo
There are currently three on-line databases on Richard Rockett Abernathy and wf Mary Sample Alexander found on ancestry.com's internet site:
One belongs to Sharyn Young, last updated 1 Nov 2001: lists 7 children, approximate birth years, but not the same children as found in Gatewood's work.
One belongs to Dwayne Gabriel, last updated 14 Oct 2001 and is essentially identical to that of Sharyn Young.
One belongs to Keelie Thomason, last updated 25 Apr 2002: lists the 8 children found in Gatewood, plus descendency of one of them (Richard Burton Abernathy).
Were I you, I'd try to email Keelie first, her entry being the most recent.