I took a look at the census records and on the 1910 census record for Butler, Greenville, S.C. John Gleen age 28 is listed with his wife Josie age 19. It says they had been married 4 years. Their children Theodore age 3 and Inez age 1. Also listed is Rance Gleen who is listed as stepfather age 72. I believe that this is John Glenn's natural father and that the census taker could have put incorrect information.
I found a 1900 census for Butler, Greenville S.C. for Rance Glenn. It lists his birthdate as 9/1845. His wife Mariah(John Glenn's mother)b.date 6/1847. son John age 20 b.date 12/1879. Bessy Tompson and Robert Franklin ages 16 and 13.
I also was able to find a Census record for Rance Glenn in 1870. It is presumed that on the census record he is still under the household of his mother. Here is how the ages and names read:
Glenn, Jennie 50
Glenn, Rance 22
Glenn, Phillip 16
Glenn, Fannie 15
Glenn, Anthony 13
Glenn, Linda 6
I also looked up Josie Durham and I found a Josie Durham under the household of Willis and Hattie Durham of Reidville, Spartanburg, S.C.
Here is a transcript of the names and ages of the Durhams.
Willis Durham born 5/1847
Hattie Durham born 6/1875
Willis and Hattie Durham had been married for 7 years and she was the mother of four children.
John Durham born 2/1877
Dasie Durham born 6/1883
Jim Durham born 9/1885
Josie Durham born 2/1891
Wayman Durham born 8/1893
Lela Durham born 6/1895
Babe Durham born 8/1899
Based on the census record and the time length of the marriage I don't think that Hattie is the mother of Josie.
Now this is where it gets interesting.
I found another census for 1880 Reidville, Spartanburg S.C. for Willis Durham. It lists Willis as age 36. His wife Allice age 29, their children were:Mattie age 11, Dora age 6, Johnnie(son)age 3, and Lamira(Daughter) age 6 months. Also listed in the houshold is Young Smith age 17.
Below the Willis and Allice Durham family is Darkas Durham, female age 64. This could possibly be Willis Durham's mother based on the ages. Her household consists of the following: sons Henry age 31, Asberry age 27, and Boris age 18; daughter Dora Hollis age 22, son in law Jack Hollis age 30 and their children Thoper (daughter) age 3 and Mathy age 2.
In the race category for Willis and Allice Durham, everyone is listed as mulatto. In the race category for Darkas Durham, she is listed as black and her children are listed as mulatto.
Below Darkas Durham there is a James Durham age 72 race white. I am wondering if James Durham may be the father of Darcas' children and/or her former slaveowner.
Also I was able to look at a death certificate for Bronzalle Glenn and it showed his birthdate as 7/28/1915 and his death date as 5/14/1941. His cause of death is listed as pulmonary tuberculosis.
Hope some of this helps you in your search.