Complex sentence: He was the eldest son of James Stewart, a direct male-line descendent of Robert II through his second son the Duke of Albany, who was created Lord Doune on 24 November 1581.
Split into simpler sentences: He was the eldest son of James Stewart, and was a direct male-line descendent of Robert II through his second son the Duke of Albany. His father was created Lord Doune on 24 November 1581.