My direct ancestor was Joseph Bryan Miles Blount.The information I have on my line differs with yours.
Joseph Bryan Miles Blount, son of Miles Blount, grandson of Bryan Blount, of Beaufort County, NC was born January 16, 1812, married Millie Owen Read January 8, 1834.Millie Owen Read was the daughter of Reuben Read and Mary Polly Alford.Millie died in Robbs, Pontotoc County, MS in 1844.Joseph Bryan Miles Blount then married Rachel Brantley on February 29, 1848.Since you have JBM Blount's death date listed as 1848, it is perplexing that he could have fathered three more children with Rachel Brantley -the last one being born in 1865.He is also listed in the 1870 Pontotoc County, MS Census.
These are the children that Joseph Bryan Miles Blount and Millie Owen Read had together: James Reading Blount b. January 17, 1836 Pickens County, AL Cassandra H. Blount b. August 20, 1837 John Reed Blount b. October 20, 1839 Mary Ann Blount b. January 9, 1842
These are the children that Joseph Bryan Miles Blount and Rachel Brantley had together:
Joseph B.Blount b. December 27, 1848 Pontotoc County, MS William H. Blount b. March 19, 1853 Charles C. Blount b. October 1865
Since it has been sometime since your original posting, if your documented information still differs with mine, please contact me.