SOURCE= http://etree10.archive.org/stream/inverurieearldog00davi/inverurieearldog00davi_djvu.txt SETON. Sir William Seton of that Ilk, of Winton, and Tranent in East Lothian, and of Winchburgh, West Lothian, had by his wife, Katherine, daughter of Sir William Sinclair of Herdmanstoun, two sons. The elder,1.) Sir John Seton of that Ilk, was ancestor of the Earls of Winton, attainted 2.)Alexander Seton, who became Gordon, by marrying, in 1408, Elizabeth the heiress of Adam de Gordon deceased, was himself the second son of Sir William Seton of Seton, and his own second son, William Seton, was the common ancestor of the Garioch Setons already mentioned.
Seton and Winton lineages and theories Alexander Seton was the son of Catharine St. Clair, daughter of Sir William St. Clair of Herdmandston, and Sir William Winton, who assumed the Seton surname; thereby William (Winton) Seton. William and Catherine had two sons and six daughters. The eldest was John and he took his father’s Seton surname and the younger aforementioned Alexander Seton who married Elizabeth de Gordon in 1408 and assumed her Gordon surname. Sir William was killed at the Battle of Chevy Chase in 1388 (Seaton 1906. pp. 57). Sir William Winton-Seton was the son of Lady Margaret Seton, the only child of Sir Alexander Seton and Margaret Murray, and Baron Alan de Winton (born about 1315, Wintoun Castle, Pencaitland, East Lothian, Scotland). Around 1347 Lady Margaret Seton was abducted by Baron Sir Alan de Winton, who lived nearby and was possibly distantly related to Lady Margaret. Tradition of several descending families dictates that the Wintons were cadets of the Seton family, who built Wintoun Castle.