Betty Washington was born 20 June 1733 to Augustine Washington (c1694-1743) and Mary Ball (1708-1789) and died 31 March 1797 of unspecified causes. She married Fielding Lewis (1725-1782) 7 May 1750 .
Betty Washington was Gen. Washington's sister. She married Col. Fielding Lewis, a second-cousin via her great-grandfather Augustine Warner II. They had several children.
Children
| Name | Birth | Death | Joined with |
| Fielding Lewis (1751-1803) | |||
| Augustine Lewis (1752-1756) | |||
| Warner Lewis (1755-1756) | |||
| George Washington Lewis (1757-1821) | |||
| Mary Lewis (1759-1759) | |||
| Charles Lewis (1760-?) | |||
| Samuel Lewis (1762-1764) | |||
| Betty Lewis (1765-1830) | |||
| Lawrence Lewis (1767-1839) | |||
| Robert Lewis (1769-1829) | |||
| Howell Lewis (1771-1822) | |||
Footnotes (including sources)
| ‡ General |