In 1777 he was married again, to Ann MacGregor, daughter of a Glasgow dye-maker, with whom he had two children: Gregory (1777–1804), who became a geologist and mineralogist, and Janet (1779–1794).
Më 1777 ai u martua sërish me Ann MacGregor, bijë e një bërësi të ngjyrave në Glasgow, me të cilin kishte dy fëmijë: Gregori (1777-1804), i cili u bë geolog dhe mineralogist dhe Janet (1779-1794).