Larkin Chew Johnston of this line? "SIR WILLIAM JOHNSTON born 19 December 1697, and died 1769 in Spotsylvania Co., Virginia. He married ANN MARY "NAN" CHEW October 12, 1723 in Spotsylvania Co, Virginia (Marriage Bond Is Dated Oct 1723, daughter of LARKIN CHEW and HANNAH ROY. She was born Abt. 1703 in Caroline Co., Virginia, and died November 11, 1742 in Port Royal, Caroline Co., Virginia."
You might try contacting DavesAncestry@hotmail.com