I do not list two sons named Isaac for Arch Ison. I only list Isaac b. ca. 1810 in Morgan Co. KY; married Anna Amelia Hamilton d/o Ned Hamilton; marriage date Dec. 4th 1832 in Morgan Co. KY.
I list Doctor s/o Isaac and Anna Hamilton Ison as being born Feb. 14, 1843 in Morgan Co. KY. I have no info on Doctor's wife. I do list that Doc's brother William Ison b. ca. 1846 in Morgan Co. KY; married Hettie Ester Hamilton on April 20, 1826 in Morgan Co. KY. I am still researching these lines-so be sure to document everything.
The Morgan Co. KY Site is here:http://www.rootsweb.com/~kymorgan/index.html
You can do a search for Ison Family Info on the front page.