John Lathrop III was born 24 April 1763 in Tolland, Tolland County, Connecticut to John Lathrop (1732-1812) and Lucy Gray (1737-1807) and died 10 December 1780 of unspecified causes.
Siblings
| Name | Birth | Death | Joined with |
| Desire Lathrop (1755-1755) | |||
| Ann Lathrop (1756-1756) | |||
| Lusalla Susanna Lathrop (1757-1827) | |||
| Baby Lathrop (1759-1759) | |||
| Prescendia Lathrop (1761-1810) | 30 January 1761 Tolland, Tolland County, Connecticut | 20 March 1810 Watertown, Jefferson County, New York | William Huntington (1757-1842) |
| John Lathrop (1763-1780) | 24 April 1763 Tolland, Tolland County, Connecticut | 10 December 1780 | |
| Elizabeth Lathrop (1765-1837) | 23 August 1765 Tolland, Tolland County, Connecticut, United States | 16 September 1837 | Andrew Steele (1763-1811) |
| Alvira Lathrop (1768-1836) | |||
| Lucy Lathrop (1770-) | |||
| Rowland Lathrop (1771-1805) | |||
| Jonathan Lathrop (1776-1776) | |||
| Molley Lathrop (1779-) | |||