Who is Bolsgar from The Wolf and the Dove and what is their importance?

Bolsgar is Wulfgar's father. He is nursed by Aislinn and soon cares for the girl, saying that he wishes he had the right to tell Wulfgar to marry her, but he gave up that place of authority in his son's life when he sent Wulfgar away. It's Bolsgar who retrieves Bryce from the old crone with whom Aislinn left him and who discovers that the boy bears the family birthmark, marking him as Bolsgar's grandson and eliminating the concern over both Bryce's and Wulfgar's parentage.