He was married to Myrtle Cowan. They had a daughter, Suzanne Newashe Underwood, who was the mother to Rebecca Lea Lewis Dean.
He had a sister, Emma Newashe, who was the grandmother to Donna Newashe McAllister. Bill was a Native American and a member of the Sac and Fox nation.[3] Newashe also played basketball and baseball at Carlisle participated in track, competing in the hammer throw. Newahse played for the Harrisburg baseball team as a pitcher and later for the Jackson, Michigan baseball team. He was a teammate of Jim Thorpe at Carlisle. He served as a pall bearer at Thorpe's death