Smith Thompson married first, Sarah Livingston (1777–1833) daughter of
Gilbert Livingston (1742–1806), a law partner of Thompson, and had four children. Second, he married Elizabeth Davenport Livingston (1805–1886), daughter of
Henry Livingston Jr. (1748–1828), and had three more children. Gilbert and Henry were siblings, making his wives, Sarah and Elizabeth, first cousins. Sarah Livingston and her husband's Supreme Court predecessor, Henry Brockholst Livingston, were also cousins via their common
Livingston family ancestors,
Robert Livingston, the Elder (1654–1728) and
Alida (née Schuyler) Van Rensselaer (1656–1727) who lived in eastern New York during the 18th century. One of his sons, Gilbert Livingston Thompson (1796–1874), married Arietta Minthorne Tompkins (1800–1837), daughter of Vice President
Daniel D. Tompkins. Their daughter, Arietta Livingston Thompson (1823–1886), was the mother of
Guy Vernor Henry and grandmother of
Guy Vernor Henry Jr. ==See also==