Boswell married his cousin, Margaret Montgomerie, on 25 November 1769. She remained faithful to Boswell, despite his frequent liaisons with prostitutes, until her death from tuberculosis in 1789. After his infidelities, he would deliver tearful apologies to her and beg her forgiveness, before again promising her, and himself, that he would reform. James and Margaret had four sons and three daughters. Two sons died in infancy; the other two were Alexander (1775–1822) and James (1778–1822). Their daughters were Veronica (1773–1795), Euphemia (1774 – c. 1834) and Elizabeth, known as 'Betsy', (1780–1814). Boswell also had at least two extramarital children, Charles (1762–1764) and Sally (1767 – c. 1768).