Hello Doug, I have just found this site and was trawling through the message board for Dunlop when I saw yours and Charles Dunlop. I am descended from Charles via his daughter Margaret Dunlop b 1765 who married my GGGGGrandfather Andrew Currie. They were all from Stewarton, Ayrshire, Scotland.
Charles's father was also a Charles b 1707 and married to a Katherine Gilmour b 1709. I don't know if they had any more children apart from Charles b 1747.
Charles and Margaret Todd had 7 children all born in Stewarton:- Margaret b 1765, Thomas b 1767, Samuel b 1769, Robert b 1771, Charles b 1773, Thomas b 1775 and Charles b 1880.
Robert b 1771 married a Mary Manson b 1773 and had one child that I can find - Charlotte b 1790.
Charles b 1780 married a Mary Carter b 1789 and had 2 sons - Charles b 1810 and John b 1811. There is more but I will have to go back into my tree to find out more.