Hi Sharon: Here's what I have; most of it is fairly well documented.
Arhibald alexander ( Sr. ), b. 1708, Cty. Donegal, Ire>Archibald ( Jr. ), b. 1771, Augusta Cty., Va.>John M. Alexander, b. 1812, augusta Cty., Va., d. 1898, Shelby Cty., Mo.
It appears that JMA left Bracken Cty., Ky. at some time after the death of his father in ca. 1830. JMA married Cordelia Gaines (of Franklin Cty., Ky.) in 1841 in Monroe Cty., Mo. JMA and CGA had the following children: Sarah Frances, b. 1844, Monroe Cty., Mo. James T., b. 1846, Monroe Cty., Mo. John D. b. 1848, Monroe Cty. Isabella, b. 1849, Shelby Cty., Mo. William F., b. 1851, Shelby Cty. Edward P., b. 1853, Shelby Cty. Robert A., b. 1855, Shelby Cty. Samuel L., b. 1860, Shelby Cty. ( this is my g granddad)
Of JMA's siblings, a sister, Mary ( Polly ), married a Robt. Wright and settled in Carroll Cty., Mo. Another sister, Anna R., married a William Sanders and settled in Monroe Cty., Mo. JMA's other siblings remained in Ky., although one did move to Indiana.
I have additional data concerning JMA's children in Missouri. Most stayed in Shelby, Monroe or Knox Cty., Mo. None of them settled in Adair Cty., although my Granddad Oscar L. Alexander was married there in 1912.
Let me know if you need further information. I haven't done much research on my g granddad, Samuel's, siblings, but I do have some data. I don't recall running across a "David" as yet.