These guys have been confusing me. Maybe picking through the discussion at soc.gen.medieval will help.
"Broughton, Overton, & Johnson families of colonial South Carolina" (August 11, 2017) < soc.genealogy.medieval >
It seems there are a number of S.C. immigrants who descend from General Robert Overton (covered in the ODNB) and his wife Anne:
Robert Overton = Anne Gardiner
Anne Overton = Andrew Broughton
Thomas Broughton = (his 1st cousin) Anne Johnson, see below ....
