Joan (The Dumb Lady) Stewart was born circa 1428 in United Kingdom to James I of Scotland (1394-1437) and Joan Beaufort (c1406-1445) and died after 16 October 1486 of unspecified causes. She married James Douglas, 3rd Earl of Angus (-1446) 18 October 1440 JL in United Kingdom. She married James Douglas, 1st Earl of Morton (-1493) 15 May 1459 JL in United Kingdom.
Children
| Name | Birth | Death | Joined with |
| John Douglas, 2nd Earl of Morton (bef1466-1513) | 1466 | 9 September 1513 England, United Kingdom | Janet Crichton (1461-) |
| James Douglas (-aft1480) | |||
| Janet Douglas (bef1481-) | |||
| Elizabeth Douglas (bef1480-) | |||
Footnotes (including sources)
| ‡ General |