Hi Janet - I cannot dispute family stories and certainly appreciate the information your relatives conveyed to you. I, too, have heard many stories from my Alabama relatives about being descended from Cherokees. All I can say is that I have researched the Blankenship, Whites and Thompson lines for years, and thus far have never found a shred of documentary evidence of Milly Blankenship (possible maiden name of Thompson) as having been a Cherokee, let alone the notion that her daughters (Anna Elizabeth, Mourning, and Jane) were her sisters who hid their Indian identities...
Milly Thompson Blankenship is my 4th great grandmother, through the female line. (My mother's mother's mother's....) When I heard about the possibility of having Cherokee heritage through this line of my family, I was, of course, excited. A few years ago, I had my mitochondrial DNA tested through Oxford University - as it turns out my mtDNA is definitely northern European - meaning that Milly and her mother were of northern European heritage. (In fact, our mtDNA shares that of a mesolithic human male skeleton found in England, "Cheddar Man".) That isn't to say Milly's mother or grandmother didn't marry Cherokee men and have children, and the Cherokee lineage came in through the males, but it does indicate that stories of Milly's mother being a full blooded Cherokee are incorrect. And while possible, at the time, it is unlikely that a white woman would have married a Cherokee man. After closely examining the information out there about Martha Fields being Milly's mother, you will notice that the birth dates are inconsistent. Many of the published stories, from certain sources, have also changed multiple times over the years and made to "fit"....not good genealogy practice.
From documentary evidence (wills, probate records, census records, military records, etc.) I can tell you that the Blankenships were indeed early settlers in Alabama. Reuben Blankenship (Sr.) was a Revolutionary War soldier. He and his son, John Blankenship, lived near each other in Shelby county in 1830, and going farther back, close to one another in Georgia in 1820. John Blankenship's heirs are mentioned twice in Reuben Blankenship's will and eventual settlement of his estate. Milly Blankenship is noted as having relinquished her dowry after the death of her husband, John. I also find it curious that a poor Cherokee woman, who had to emigrate away from her home, would have had a marriage dowry. Again, it is possible, but highly unlikely given the circumstances.
I don't know if Milly's maiden name was Thompson and if she was the daughter of John Thompson and a Martha Fields - I've never found any historical records or documentary evidence. It is that primary source record information I am seeking. There were Thompson and Fields families who lived in NC and TN, and both do indeed have Cherokee connections - yet in the Cherokee census records of 1834, 1835, and 1837, Cherokee rolls, and military muster records, both families wound up in AR, OK, and TX - the do not show up on the Alabama Cherokee census. And yes, there was a John Blankenship who lived in the same Cherokee territory as the Fields, Whites, Ridge and Ross in NC in 1830 - but it surely doesn't appear to be the same John Blankenship who lived at the same time, with females the ages of Milly, Anna Elizabeth, Mourning, and Jane, in Shelby county, AL, near Reuben Blankenship, Sr.
The Blankenships are a very large and tangled family. I am attempting to sort out the truth from the family tales and am seeking the answers through definitive records. If you have any letters or other records I would love to have copies and will gladly reimburse you for postage and copying expense.