Johnson Addis is listed in the 1860 census as being in Menallen Twp., Fayette Cty. His age is shown as 53, so he was born c. 1807. His wife is Martha, age 49. Others in the house are listed, but I'm not sure who were children and who were grandchildren. One who I think was a child was William, age 31; Malachi, age 7 is also listed, and I think he was William's child. Also listed: Elizabeth (21), Hiram B. (17), Martha A. (15), Johnson H. (12), John H.(?)(10. Johnson was listed as a day laborer. Johnson is also shown in tax records of Franklin Twp., Fayette Cty., as early as 1827 - also as a laborer.
In a history of Fayette County, to which I don't have the citation, Johnson is mentioned as a child of Jonathan Addis (born c. 1760 in Bucks Cty.), who married Elizabeth Laughead.