Sir William Stewart of Dalswinton & Garlies was born in Scotland to John Stewart and Marion Stewart and died circa 1479 Scotland of unspecified causes.
"Sir William Stewart, of Dalswinston and Garlies, obtained the estate of Minto in 1429, after much opposition from the Trumbulls, the former possessors. He was living in the year 1479, and had issue." --A Genealogical and Heraldic Dictionary of the Peerage and Baronetage of the British Empire, Volume 42, Part 1
Children
| Name | Birth | Death | Joined with |
| Andrew (-bef1479) | |||
| Alexander Stewart, 2nd of Garlies (-aft1479) | Scotland | 1479 Scotland | Elizabeth Stewart (-aft1479) |
| Thomas Stewawrt of Minto | |||
| Walter Stewart of Tonderghie | |||
Siblings