Wikipedia
Matlalatzin
Matlalatzin was a Queen of Tenochtitlan as a wife of the king Chimalpopoca, and was a princess by birth. She was a daughter of Quaquapitzahuac, king of Tlatelolco, and sister of the king Tlacateotl and queen Huacaltzintli. She bore seven children.
She and her husband were cousins.