He had a relationship with Lady Margaret "Margaretha" Leslie aka Heiress of Galston.
Child(ren):
The heir:
David fitz Walter fitz Gilbert, Knight, granted the royal barony of Cadzow by David II, not known to have used the surname de Hamilton (or any other), fought at Halidon Hill and at Durham (where he was taken prisoner 1346), one of the Scottish magnates who arranged the settlement of the Crown on Robert III 1371, d between 1374 and 1378. He m Margaret dtr of William de Ross, 5th Earl of Ross by whom he had four sons:
..A1 David, his heir [see below]
..A2 John Hamilton of Fingaltoun, Knight, ancestor of the Hamiltons of Preston
..A3 Walter Hamilton, claimed as ancestor of the Hamiltons of Cambuskeith and Hamiltons of Sanquhar in Ayr
..A4 Alan Hamilton of Larbert, a substantial beneficiary of the 1420 Testament of Sir Robert Maxwell of Calderwood, whose dtr he may have married.
..a1. A daughter reported to have m Simon Roberton of Earnock.
www.baronage.co.uk/bphtm-03/hamilton.html
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