Your note that William H[oward] Oglesby had a probable brother, Charles C., got me started.I found his online World War I draft registration at Ancestry.com--Charles Clint Oglesby, age 44, b. May 19, 1874, self-employed butcher in McClain Co., Oklahoma.He listed his nearest relative as F. A. Oglesby, Route 1, Overall, Rutherford Co., Tennessee.[Note:I found no draft registration for William H. Oglesby.]
Clint is found in the 1900 Rutherford Co. census, married to Susie; in 1910, he is listed as Charles C. Oglesby, wife Susie, in Greer Co., Oklahoma, on the same page as the enumeration for William H. and Fannie Oglesby's family.In 1920 he is working in McClain Co., Oklahoma; Susie is apparently dead or divorced; and the children are back in Rutherford Co., Tennessee, living with Susie's father, W. J. Owen.
The 1880 Rutherford Co. census lists Franklin Oglesby, wife Martha, sons William , Clinton , and Joseph , proving that William and Clinton were brothers.The whole family was born in Georgia; Franklin's parents are noted as b. North Carolina, Martha's parents are both listed as b. Tennessee.
The 1870 Whitfield Co., Georgia census lists Frank Oglesby, age 22, "at school," living in the household of William Tucker, his soon-to-be father-in-law.
The 1860 Whitfield Co. census enumerates Franklin Oglesby, 13, along with his siblings, in the household of S. and Nancy Oglesby.[Census states whole family was born in North Carolina.]
The 1850 Murray Co., Georgia census lists household of Shedrick and Nancy Ogilsby.Franklin A., 6, is noted to have been born in Georgia.[Between 1850 and 1860 a part of Murray County was taken when Whitfield Co. was created, so the family did not necessarily physically move to Whitfield.]
The 1840 Surry Co., North Carolina census lists Shadach Oglesby, age 30-40, as a head of household.
Shadrach's father, Micajah, left a will in Surry Co. in 1828, which specifically names Shadrach as one of his children.
Some sources state Micajah was born in Virginia about 1754, a son of William and Ann Perkins Oglesby, and was married to Frances Black. I have seen no direct evidence that would confirm these assertions.
So: this is a synopsis of my detective work for you.I have actually seen all the census images and draft registrations cited, but will leave it up to you to get actual hard copies if you so desire.I do not have any further information I can send you.[Please bear in mind:this is not even my branch of the Oglesby line!]