Timna, a concubine of Esau’s son Eliphaz, bore Amalek to Eliphaz. These were the sons ¹  of Esau’s wife Adah.

Now Saul had a concubine named Rizpah daughter of Aiah. Ish-bosheth ¹  said to Abner, “Why did you have sexual relations with ²  my father’s concubine?” ³ 

The sons to whom Keturah, Abraham’s concubine, ¹  gave birth: Zimran, Jokshan, Medan, Midian, Ishbak, Shuah. The sons of Jokshan: Sheba and Dedan.

Caleb’s concubine ¹  Ephah bore Haran, Moza, and Gazez. Haran was the father of Gazez.

While Israel was living in that land, Reuben had sexual relations with ¹  Bilhah, his father’s concubine, and Israel heard about it. Jacob had twelve sons:

In those days Israel had no king. There was a Levite ¹  living temporarily in the remote region of the Ephraimite hill country. He acquired a concubine ²  from Bethlehem ³  in Judah.