Euphemia was born on an unknown date in Scotland, the daughter of David Stewart, Earl Palatine of Strathearn and Caithness.
In about March 1386 her father died and she became suo jure Countess of Strathearn and Caithness.
[2] He was killed on St Laurence Day (10 August) 1413, near Crieff, by Sir John Drummond of Concraig, Steward of Strathearn, in a skirmish between them arising out of the Earl-consort's dissatisfaction with Sir John's official duties.
[3] The Countess survived him, and received papal dispensations to marry Robert Stewart of Fife, eldest son of Murdoch Stewart, Duke of Albany (on 4 May 1414), and subsequently Robert's brother Walter (5 September 1415),.
[4] She is alleged in Scots Peerage to have married Sir Patrick Dunbar of Bele, but this is erroneous: this was proved in 2009 to have been a second marriage of Euphemia Stewart, daughter of John Stewart of Ralston and the mother of Countess Euphemia's husband Sir Patrick Graham.