Genesis 28:6-9
6 Now Esau learned that Isaac had blessed Jacob and had sent him to Paddan Aram to take a wife from there, and that when he blessed him he commanded him, “Do not marry a Canaanite woman,”
7 and that Jacob had obeyed his father and mother and had gone to Paddan Aram.
8 Esau then realized how displeasing the Canaanite women were to his father Isaac;
9 so he went to Ishmael and married Mahalath, the sister of Nebaioth and daughter of Ishmael son of Abraham, in addition to the wives he already had.