Charles Ellicott Commentary Genesis 36:22

"And the children of Lotan were Hori and Heman. And Lotan`s sister was Timna." — Genesis 36:22 (ASV)

Timna. —Not the Timna mentioned in Genesis 36:12, because she is described here as sister of Lotan the brother of Zibeon, who was grandfather of Aholibamah, Esau’s wife. But the Timna mentioned there was the concubine of Esau’s grandson, and junior by four generations.