Martha Cobb Tinkham Knowles was born 6 February 1682 in Barnstable, Barnstable County, Massachusetts to James Cobb (1634-1695) and Sarah Lewis (1644-1735) and died 31 October 1763 Chatham, Barnstable County, Massachusetts of unspecified causes. She married Ephraim Tinkham (1682-1713) 24 June 1708 in Middleborough, Plymouth County, Massachusetts. She married Richard Knowles (1688-1769) 1714 in Massachusetts.
Children
| Name | Birth | Death | Joined with |
| Richard Knowles (1715-1736) | |||
| Mercy Knowles (1717-1758) | 4 August 1717 Chatham, Barnstable County, Massachusetts | 14 May 1758 Chatham, Barnstable County, Massachusetts | George Godfrey (1707-1768) |
| James Knowles (1719-1781) | |||
| Cornelius Knowles (1722-1794) | |||
| Rebakah Knowels (1723-1784) | |||
Siblings
| Name | Birth | Death | Joined with |
| Mary Cobb (1664-1737) | |||
| Sarah Cobb (1666-1742) | |||
| Patience Cobb (1668-1747) | |||
| Hannah Cobb (1671-1739) | |||
| James Cobb (1673-1757) | |||
| Gershom Cobb (1675-1751) | |||
| John Cobb (1677-1754) | |||
| Elizabeth Cobb (1680-1714) | |||
| Martha Cobb (1682-1763) | 6 February 1682 Barnstable, Barnstable County, Massachusetts | 31 October 1763 Chatham, Barnstable County, Massachusetts | Ephraim Tinkham (1682-1713) Richard Knowles (1688-1769) |
| Mercy Cobb (1685-1732) | |||
| Thankful Cobb (1687-1771) | 10 June 1687 Eastham, Barnstable County, Massachusetts | 7 April 1771 Truro, Barnstable County, Massachusetts | Thomas Paine (1682-1745) |