With respect to Herschel Walker's claim that his grandmother, or was it his great-grandmother, was somehow linked to the Cherokee, he may actually be on to something there. It turns out that the Cherokee nation, before and even after it was forcibly moved to Oklahoma, practiced slavery, including owning many African slaves:
How Native American Slaveholders Complicate the Trail of Tears Narrative
http://www.smithsonianmag.com/smithsonian-institution/how-native-american-slaveholders-complicate-trail-tears-narrative-180968339/..
And further, when the slaves were freed after the Civil War, many of those who had been owned by Cherokee families were basically adopted by those same families, even if they had no Cherokee blood. Since these African slaves and their descendants had been part of this society for so long and since they had also suffered the forced displacement to Oklahoma on the 'trail of tears' many of the Cherokee came to consider them basically part of their tribe, if not legally, at least socially:
The Cherokee Nation acknowledges that descendants of people once enslaved by the tribe should also qualify as Cherokee
http://www.cnn.com/2021/02/25/us/cherokee-nation-ruling-freedmen-citizenship-trnd/index.html

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