A fight had broken out that led to the Arapaho chief being stabbed, and the Atsina chief was killed in retaliation. He found the boy on a Friday, which was the nexus of his name from that point forward.
A confrontation arose that resulted in the Arapaho chief's death by stabbing, and the Atsina chief's demise in retaliation. The boy was discovered on a day that would become significant to him, marking the beginning of his name.