David II was the only surviving son of Robert the Bruce, when Bruce died in 1329. David was born in 1324, when Robert was 50. When David was 4, he was married to 7 year old Joan, sister of Edward III of England. On November 24, 1331, David was crowned at Scone, as King of Scotland.
David is included in Scott's Tales of a Grandfather: Liberation and Death of King David II. David died in Edinburgh Castle in 1371, without issue. The Bruce line thus ended, and the Stuart line began with the accession of Robert II of Scotland. King Robert Stuart was the son of Marjorie, who was Robert the Bruce's daughter, and Walter Stuart.