John Anderson Jr. was born on 13 October 1690 in Dunfermline, Fife, Scotland, the son of John Gaal Anderson and Margaret Jean Henderson. A profile for him on geni.com states his birth as 22 September 1690 in Fenwick, East Ayrshire, Scotland; this information is probably a different John Anderson.
Notes on John: A Scots Presbyterian who migrated to America through Ulster, Ireland. One researcher wrote that an old family Bible had John's family being from Lanark, Scotland. He entered the Port of Philadelphia with wife Margaret and one or two sons. He lived in Pennsylvania, Lancaster County and probably Chester County, Nottingham Township from 1736-1738.
John married Margaret Jean Campbell in about 1710. Their children are listed in various genealogies as:
Dates are approximate.
John died on 10 November 1765 in Augusta, Virginia. A profile for him on Our Family Tree states his death as 8 December 1740 in Somerset, Pennsylvania.
"Scotland Births and Baptisms, 1564-1950", database, FamilySearch (https://www.familysearch.org/ark:/61903/1:1:XTNM-F3X), John Anderson, Dunfermline, Fife, Scotland, Oct. 1690.