Sinfjotli

Sinfjotli was the son from the incestuous relation of Sigmund and his sister Signy. Sinfjotli was the half-brother of Sigurd, Helgi and Hamund.

Sinfjotli was born as the result of Signy, who secretly disguised herself as a young witch, who visited and slept with her brother. Signy gave her brother a son who would help them avenge their father and brothers' death. Sigmund and Sinfjotli did not know they were father and son until Signy's death. Sinfjotli helped Sigmund with his vengeance, and killed Siggeir and his followers.

He followed his father to Hunland, when Sigmund became king. His father married Borghild and had two sons, Helgi and Hamund. Though Sinfjotli helped Helgi in several wars, his stepmother continued to hate him. Sinfjotli was aware of her hatred. She tricked her husband to drinking two cups of drugged wine meant for Sinfjotli. The third cup contained poison. Sigmund, thinking that there was nothing in the third cup, he told his son to drink it. Sinfjotli drank poisoned wine and died.

Sigmund took his son's body to the fjords where he met a ferryman (Odin). The ferryman offered them passage across the fjords but could only carry one person at a time. In the middle of the fjords the boat and Sinfjotli's body disappeared before Sigmund's eyes. Sigmund then returned home and banished Borghild for murder of his son. Sigmund would marry again.