In 1823, Chapin married Mary Crosby.[1] The couple had four children: Louisa, Helen, Charles, and Marshall.[1]
Detroit
In 1819 Chapin moved to Detroit, and, with the help of his uncle, established the first drugstore there,[1] as well as going into private practice as a physician.[2] He was soon appointed physician for Fort Shelby.[3] He went into public service, serving as an alderman in 1826 and 1827 and mayor in 1831 and 1833.[1] He was appointed City Physician during the cholera epidemic of 1832, and served as same during the second outbreak in 1834.[1]
Marshall Chapin died of heart disease on December 26, 1838.[2] His drugstore continued in business under his son-in-law's name, and others, well into the 1880s.[2][4]