Esau took his wives of the daughters of Canaan; Adah the daughter of Elon the Hittite, and Aholibamah the daughter of Anah the daughter of Zibeon the Hivite. Genesis 36:2Apparently, Esau also married Anah's daughter, Aholibamah. So Esau was married to a mother-daughter pair, and therefore, according to the Bible (Leviticus 20:14), all three should be burned to death.
And these were the sons of Aholibamah, the daughter of Anah the daughter of Zibeon, Esau's wife. Genesis 36:14
And these are the sons of Aholibamah Esau's wife; duke Jeush, duke Jaalam, duke Korah: these were the dukes that came of Aholibamah the daughter of Anah, Esau's wife. Genesis 36:18
And the children of Anah were these; Dishon, and Aholibamah the daughter of Anah. Genesis 36:25
These are the sons of Seir the Horite, who inhabited the land; Lotan, and Shobal, and Zibeon, and Anah. Genesis 36:20
And these are the children of Zibeon; both Ajah, and Anah. Genesis 36:24
And the sons of Seir; Lotan, and Shobal, and Zibeon, and Anah, and Dishon, and Ezar, and Dishan. 1 Chronicles 1:38
The sons of Zibeon; Aiah, and Anah. 1 Chronicles 1:40To summarize: Anah and her daughter were married to Esau. Anah was also the son of Zibeon, who was Anah's brother and father.