Darby II, was the son of Capt. Darby Lux I (1695–1750) and Ann Saunders (1700–1785). Ann was the daughter of Robert Saunders (d. 1755) and Rebeckath Groom (d. 1752). Darby Lux I, was the son of William Lux II, Vicar (ca. 1657-1714) and his wife Elizabeth. William II, was the son of William Lux I and his wife Wilmot (d. 1703).