Mary Howe Barnes was born 14 January 1727 in Marlborough, Middlesex County, Massachusetts to Abraham Howe (1699-1781) and Rachel Rice (1703-1782) and died 25 March 1813 Marlborough, Middlesex County, Massachusetts of unspecified causes. She married Frederick Barnes (1727-1778) 22 March 1749 in Marlborough, Middlesex County, Massachusetts.
Children
| Name | Birth | Death | Joined with |
| Asa Barnes (1756-1812) | 28 June 1756 Marlborough, Middlesex County, Massachusetts | 1812 Hillsborough, Hillsborough County, New Hampshire | Matilda Woods (1757-) |
| Benjamin Barnes (1752-1812) | |||
| Lucy Barnes (1767-1839) | |||
Siblings
| Name | Birth | Death | Joined with |
| Eunice Howe (1725-) | |||
| Mary Howe (1727-1813) | 14 January 1727 Marlborough, Middlesex County, Massachusetts | 25 March 1813 Marlborough, Middlesex County, Massachusetts | Frederick Barnes (1727-1778) |
| Persis Howe (1728-1760) | |||
| Abraham Howe (1730-1770) | 14 December 1730 Marlborough, Middlesex County, Massachusetts | 12 March 1770 | Lydia Stow (1732-) |
| Asa Howe (1733-1793) | 30 November 1733 Marlborough, Middlesex County, Massachusetts | 1 February 1793 Marlborough, Middlesex County, Massachusetts | Rachel Goddard (1732-1814) |
| Abner Howe (1735-1818) | |||
| Adonijah Howe (1738-1800) | |||
| Anna Howe (1739-1752) | |||