I have been working extensively to untangle all the Millers of Coosa County and clarify their kinships. I began with my ancestor Andrew Jackson Miller b 1834 and went back to the SC census records for his grandfather, Charles Miller.

This is what I determined:
A. There are 4 Henry Millers from Coosa County with birth years of 1814, 1834, and 2 born in 1868.
B. There are 5 James Millers from Coosa with birth years of 1814, 1840, 1844, 1846, and 1860.
C. There are 2 John McBride Millers: Sr b 1807 SC and Jr, b 1841 GA
D. There are 3 John Thomas Millers from Coosa with birth years of 1845, 1847, and 1877
E. There are 2 Wm Millers from Coosa with birth years of 1840 and 1854. There is also a William Miller in 1830-1840's who did business in Coosa, but does not appear to be related to Charles Miller's descendants.
F. There are 3 Mary Millers [maiden name] 2 b 1851 and the 3rd b 1862
This is why it is hard to discern which Henry, James, Mary, or John McBride Miller is being queried. With that said, below is what I learned from census data for Charles Miller, b in Ireland abt 1760 and Nancy b in Ireland abt 1780 and their descendants. She is most likely his 2nd wife.
Census records for 1790 - 1880 from SC, GA, and AL were searched.


The paternal grandfather of AJ Miller was Charles Miller immigrant from Ireland to SC. He had the following children by wife Nancy:
1. John McBride Miller Sr b 1807 in SC [probably Chester County]
2. daughter b 1810-1815 name unknown [probably Chester County]
3&4. twin sons, James and Henry b 1814 [probably Chester County]

He likely had 5 children by a previous wife:
1. William b 1783
2. Elizabeth b 1785
3. Charles b 1787
4. Robert b 1789
5. NancySusan b 1791
Extensive exam of the census data for 1790-1840 SC and GA agrees with the above 9 children, however there is no way to prove the names and actual birth years of those born 1783-1791 and daughter b 1810-1815 without other documents to confirm this. Census records up to 1840 only recorded the names of the heads of households and age ranges of those living in the households. Most likely Charles Miller immigrated into SC in 1806, but it could have been 1801. That's the closest I could determine from the census records and immigration lists.

Charles and Nancy's sons, John McBride Sr and James moved to Coosa County, AL around 1850. Henry and Martha are in Cherokee Co GA in 1850 census and did not move to Coosa until abt 1859. Charles Miller died in Henry County, GA between 1830-1840 and Nancy [Adams?] Miller died in Henry or Cherokee County, GA between 1840-1850.

Coosa County Miller families:
John McBride Miller [aka JMC Miller], Sr married Martha Gibson in Henry County, GA in 1833 and they had the following children:
1. Andrew Jackson b 1-1-1834 Henry County, GA
2. Nancy b 1838 Henry County, GA
3. William b 1840 Henry County, GA
4. John McBride [aka JMC Miller], Jr b 1-11-1841 Henry Co, GA
5. James Monroe b 3-14-1846 Henry Co, GA
6. Charles T b 3-20-1848 Henry Co, GA
7. Mary Ann b. 3-27-1851 Coosa Co, AL

Henry Miller b 1814 SC married Martha S. Bell b 1825 GA in Cherokee Co, GA on 8-17-1843 and they had the following children:
1. James Henry b 1844 GA
2. Madison H. b 1846 GA
3. John Thomas b 1848 GA
4. Mary b 1851 GA
5. Jefferson b 1852 GA
6. William b 1854 GA
7. Levi b 1857 GA
8. Joshua b 1862 AL
9. Adolphus b 1865 AL
10. Henry b 1868 AL

James Miller b 1814 SC and Mary Gibson [sister of Martha Gibson, who married JMC Miller] b 1819 GA married abt 1835 and had the following children:
1. Henry Walter b 1836 GA
2. James b 1840 GA
3. Martha b 1842 GA
4. John Thomas b 1845 GA
5. Charles T b 1847 GA
6. Robert Anderson b 1852 AL

From studying the census data in SC I am inclined to believe that Charles had family already living in Chester County, SC prior to his immigrating there. The common family names seem to be Charles, William, Robert, John, and Elizabeth, although those are common names so one can only speculate.

In 1840 Henry County, GA, JMC and Martha Miller live next door to a Francis Miller [head of house with 7 or 8 children]. It's unlikley that this is the sister b 1810-1815. There is a 40-50 yr old male living there so the assumption is that he is the head of house named Francis Miller. The kinship of JMC to this family is not known, perhaps an uncle.