Your answer can be found in Hinshaw's Quaker records for Virginia. JOHN BROWN s. Wm. & Elizabeth (Farquhar) Brown of Loudoun Co. VA, prcf Fairfax MM VA 5-5-1791; clear; 29-8-1791 dtd 25-6-1791 to marry Ann Hirst; ltm; m. 5-5-1791 @ Goose Creek MH, Loudoun Co. VA, ANN HIRST dt John & Mary (Heston) Hirst of Loudoun Co. VA & of Fairfax MM, VA & formerly of Wrightstown MM PA.

WILLIAM BROWN (1722-1794) m. Elizabeth Farquhar 26-11-1757; s. of RICHARD BROWN (1693-1745) by lst wife HANNAH REYNOLDS; that Richard Brown was son of WILLIAM BROWN (the immigrant) by his second wife ANN MERCER.