Nahor’s concubine, whose name was Reumah, gave birth to Tebah and Gaham and Tahash and Maacah.

but to the sons of his concubines [Hagar and Keturah], Abraham gave gifts while he was still living and he sent them to the east country, away from Isaac his son [of promise].

While Israel was living in that land, Reuben [his eldest son] went and lay with Bilhah his father’s concubine, and Israel heard about it.

Now Jacob had twelve sons—

And Timna was a concubine of Eliphaz, Esau’s son; and she bore Amalek to Eliphaz. These are the sons of Adah, Esau’s wife.