David Bruce, aged five, became king on 7 June 1329 on the death of his father Robert. Walter the Steward had died earlier on 9 April 1327, and the orphaned eleven-year-old Robert was placed under the guardianship of his uncle, Sir James Stewart of Durrisdeer, who along with Thomas Randolph, Earl of Moray, and William Lindsey, Archdeacon of St Andrews were appointed as joint Guardians of the kingdom. David's accession kindled the second independence war which threatened Robert's position as heir. In 1332 Edward Balliol, son of the deposed John Balliol, spearheaded an attack on the Bruce sovereignty with the tacit support of King Edward III of England and the explicit endorsement of 'the disinherited'. Edward Balliol's forces delivered heavy defeats on the Bruce supporters at Dupplin Moor on 11 August 1332 and again at Halidon Hill on 19 July 1333, at which the 17-year-old Robert participated. Robert's estates were overrun by Balliol, who granted them to David Strathbogie, titular earl of Atholl, but Robert evaded capture and gained protection at Dumbarton Castle where King David was also taking refuge. Very few other strongholds remained in Scottish hands in the winter of 1333—only the castles of Kildrummy (held by Christina Bruce, elder sister of Robert I and wife of Andrew Murray of Bothwell), Loch Leven, Loch Doon, and Urquhart held out against Balliol forces.