By way of interpolation, the historian of the Sacred Record informs us that the "children of Amulon and his brethren, who had taken to wife the daughters of the Lamanites, were displeased with the conduct of their fathers."
Evidently those Nephites who later became Lamanites continued to pursue the wicked ways they had walked as priests of Noah. Their children were ashamed to be called by the names of their fathers, and therefore chose to be called Nephites, and they took upon themselves the name of Nephi. Afterwards they were numbered among the Nephites.