Milcah was a woman of ancient Mesopotamia and an ancestor of the patriarch Jacob. Milcah was born to Haran, who had another daughter, Iscah. This Haran seemed to be different from Haran, Abraham's brother, who had a son, Lot. (Gen. 11:27,29.) Haran, Abraham's brother, died in Ur before his father Terah. (Gen. 11:28.) Milcah married Nahor, another of Abraham’s brothers. (Gen. 11:29.)
There is a prevalent assumption that the two men with the name Haran are indeed one person. If that is true, then Milcah married to her uncle. Although Leviticus would later outlaw marriages between aunt and nephew (Lev. 18:14, 20:19), it did not rule out marriage between uncle and niece. (See, e.g., Gunther Plaut, The Torah: a Modern Commentary, 881. New York: UAHC, 1981.) The Talmud approved of a man who married his sister’s daughter. (Yevamot 62b-63a.) And in the Talmud, Rabbi Isaac equates Milcah’s sister Iscah with Sarah (then Sarai), who married Abraham (then Abram), who was also their uncle. (Sanhedrin 69b.) Thus, according to Rabbi Isaac, the two sisters, Milcah and Iscah, married the two brothers, Nahor and Abraham.
Milcah and Nahor had eight children, Uz, Buz, Kemuel, Chesed, Hazo, Pildash, Jidlaph, and Bethuel. (Gen. 22:21.) Targum Jonathan says that Providence granted Milcah conception in the merit of her sister Sarah. (Targum Jonathan to Gen. 22:20.) Nahor also had four children by his concubine, Reumah. (Gen. 22:24.)
Milcah’s son Bethuel moved to Padan-aram and fathered Rebekah. (Gen. 22:23; 24:15, 24, 47.) Milcah’s granddaughter Rebekah then married Milcah’s nephew Isaac (Gen. 24:67; 25:20), and gave birth to Jacob (Gen. 25:21–26), who became Israel. (Gen. 32:28; 35:10. According to a Midrash, Milcah was the forbearer of all the prophets in the world. (Yalkut Shimoni Balak 22:20.)