Some of this information I have dug up myself and some came from Carolyn Wellborn Haskins who has done extensive research on the Wellborn family name.
This is the Bible Record of Elijah Wellborn :
Elijah (Elias Anderson) Wellborn b. June 10, 1787 NC m. c. 1810 D. June 25, 1864 Forsyth Co., GA.
m. Agnes Ann Craig (Also spelled Agnes)
b. June 7, 1797 Pickins Co., SC d. Apr 29, 1865 Forsyth Co., GA
1.Alston B. b. Aug 31, 1811 Pickins Co., SC m. Winnifred "Winney" L. ukn
2. A. E. b. Mar 26, 1813 Pickins Co., SC m. Mary W. D. April 7, 1842
3. Elizabeth b. Nov 10, 1815 b.Pickins Co., SC d. Dec 28, 1844 (may have married a Samples)
4. Chapley Booth b. Jan 8, 1817 b. Knoxville, TN m. Mary Anne Foster Forsyth Co., GA Dec 10,1837 had a son Olin Wellborn who was a judge in CA well renoun there.
5. Mary B. b. Jan 24, 1819 m. Aaron T. Welborn or Aaron (G.) m. Forsyth Co., GA March 6, 1835
6. Theodocia C. b. Dec 27, 1821 m. David Walker July 7, 1846 Forsyth Co., GA
7. Sarah Ann b. Oct 24, 1823 m. Elijah J. Mashburn Dec 8, 1839 Forsyth Co., GA
8. Savallia S. b. Jan 13, 1826 d. May 1869
9. Sebron b. Jan 13, 1826 D. Nov 17, 1836 Forsyth Co., GA
10. J. B. b. Feb 13, 1828
11. Martha Craig b. Dec 27, 1829 m. Lawson Henderson Hope Dec 30, 1849 Forsyth Co., GA d. Feb 26, 1870 Fulton Co., GA
12. Pierce Mashburn b. Nov 5, 1836 Forsyth Co., GA (Pierce Mashburn Wellborn) m. Harriet Isabelle Bailey b. Sept 23 1832 Gwinette Co., GA. ."They married in the home of John T. Bailey. The minister was John Reese a minister of the gospel of the M.E. church." These notes are from the Original Bible of P.M. Wellborn, on a "Certificate of Matrimony" page in the Bible.He died Nov 9, 1925 Abliene , TX. and Harriet Isabelle died August 1, 1913 in Abilene, Texas. At the time of their deaths they were living in the home of their Son with their daughter-in-law Mary Elizabeth (Murphee) Wellborn and her children.Their son William Hope had a stroke and died in 1915.
Pearce Mashburn Wellborn, known as P.M. was born Nov 5, 1836 in Atlanta or Forsyth County, Ga. He died Nov 8, 1925 in Abilene, Taylor County, TX.
His wife was Harriet Isabel Bailey Wellborn. Their children were:
John Elijah Wellborn (1858 - Feb 27, 1885),
William Hope Wellborn, born June 16, 1860 and died June 1 1915,
Henry P. Wellborn (died August 10, 1935)
and Olin Orestes Wellborn. I have no birth or death of Olin Orestes but your 1865 date is about right. He probably was born in Ga. and came to Texas as a very young boy. I know the family was in Texas in Johnson County in 1877. Both in the Bibles of my Grandfather and Great Grandfather are the notes "Olin O. left home November 1889.
After the death of his son William Hope Wellborn, P.M. was cared for by his daughter-in law, Elizabeth Murphee. In Aline Parks, "The Coming West," issued Sept 19, 1970 by the Ranch Headquarters Association in Snyder Texas by Mrs. Ophelia Dorward Blanchard, and Mr. & Mrs. J. A. Parks Jr. "P. M. Wellborn and wife and two sons and their families moved to Scurry County, Texas in 1889. The two sons were Will H. Wellborn and Henry P. Wellborn." (One source indicates they moved from Brown County TX, but the online edition of the 1880 census does not list them there.) "Bison Baptist Church was organized under a tree on Bull Creek, near Snyder, Texas. Members were Mr. and Mrs. P. M. Wellborn and their two sons and their wives -- Mr. and Mrs. W. H. Wellborn and Mr. and Mrs. H. P. Wellborn. [I have no dates on this information but in Mama (Mary Elizabeth Murphee)Wellborn's obituary, it indicated that she moved from Snyder in 1905 and that she was the last charter member of Knapp Baptist Church near Snyder."
The following information is something I copied from a message board some time ago as I was trying to put Olin O. together.
I recently learned that the father of my great grandfathers' name is Olin Orestes Wellborn (which you must agree is a strange name).Olin Orestes Wellborn supposedly born in Texas had been married, divorced and remarried a Susan Crutcher of Tennessee. They then had 3 sons the middle being my great-grandfather born in 1905 in St. Louis, MO. Would you happen to know whether there is any connection between my Olin Orestes Wellborn and yours. Also the three sons were named Olin, Orin Crutcher, & Orville Bailey Wellborn. First wife may have been named Peace. Thank you
Here is a little more Olin stuff but not the same guy just the same family. Olin Wellborn CSA son of Chapley Booth Wellborn died in Los Angeles, CA on Dec 6, 1921 and is buried in Rosedale Cemetery. He was a US Representative from TX 1879-87 and Judge of US District Court 1895-1915 in CA.
The name Olin Wellborn appears in the line of Jonathan Welborn (1763 NC) son of Edward Welborn and Martha his wife- Jonathan's son Cordial Thomas Wellborn had a son Olin Wellborn who died in the Civil War. From GA also Coweta Co.