Abimelech, in both cases (Genesis ch.20 and 26).
Note that "Abimelech" was a title (like "Pharaoh"), not a personal name. Since many decades passed between the two incidents, it was probably two different "Abimelechs."
Esau (Esav) and Jacob (Yaakov) were twins. Esau was the first to be born, with Jacob emerging literally on the heel of his brother.
If you're talking about the figures in the Biblical book of Genesis, then let's back up a few generations and try to get it straight: -- Abraham migrated to Israel late in his life. His children included his son Isaac. -- Isaac lived his whole life in Israel. His children included his son Jacob. -- Jacob left Israel, worked for his uncle for 20 years, and returned to Israel. He had 12 sons and one daughter. Joseph was one of the sons. Dina was the daughter. Joseph was forcibly taken to Egypt as a teen-ager. Years later, Jacob and the rest of his family migrated to Egypt during a famine. All of them died there. Their descendants left to return to Israel only after another 230 years, and only a few of them completed the return trip. -- Joseph had two sons: Ephraim and Menassah. There were no daughters. The sons were born, lived, and died in Egypt.
Isaacs mother was Sarah, that is Abrahams wife.
Az Abrahams has: Performed in "34 South" in 2004. Played Sedick Isaacs in "More Than Just a Game" in 2007. Played Jeff Levine in "Innocent Times" in 2008. Played Pin Stripe in "Doomsday" in 2008. Played King Hammurabi in "The Scorpion King: Rise of a Warrior" in 2008. Played Sadiq in "Darfur" in 2009.
Stan Isaacs's birth name is Stanley Isaacs.
Sonya Isaacs's birth name is Sonya Melissa Isaacs.
Tim Isaacs is 6'.
John Isaacs died in 2009.
Elijah Isaacs died in 1799.
Nathaniel Isaacs died in 1872.
Nathaniel Isaacs was born in 1808.
Jon Isaacs was born in 1949.
Alick Isaacs was born in 1921.
Alick Isaacs died in 1967.