Prophet Ishaq (Peace be upon Him) was the second son of Prophet Ibraheem(Peace be upon Him). His English nameis Isaac. Ishaq (AS) was the father of Bani Israel. And his elder brother was Prophet Ishmael (AS).
When Ibraheem saw his life coming to a close, he wanted his 2nd son Ishaq (AS) to get married, Ishaq (AS) was the father of the Jews and Ishmael (AS) was the father of the Arabs. He didn't want Ishaq to marry from the Canaanites, because they were pagans, so he sent a trustworthy servant to Haran (Iraq) to search for a wife for Ishaq (AS).
When the servant arrived, his eyes fell upon Rebekah. Rebekah bint Bethuel ibn Nahoor.Nahoor was the brother of Ibraheem (AS), Ibraheem (AS) had two brothers, one was called Harran and the other was Nahoor.Nahoor was the grandfather of Rebekah.
Harran was the father of prophet Lut (AS). So prophet Lut (AS) was the nephew of Prophet Ibraheem (AS).
Ishaq (AS) got married to Rebekah and she bore him two sons who were twins. Their names were Esau and Jacob.
The Quran does not give details of Isaac's life (pbuh), but reliable Quranic commentators mentioned that when Prophet Ibraheem felt that his life was drawing to a close, he wished to see Isaac married. He did not want Isaac to marry one of the Canaanites, who were pagans, so he sent a trustworthy servant to Haran in Iraq to choose a bride for Isaac. The servant's choice fell upon Rebekah Bint Bethuel, Ibn Nahor (who was a brother of Ibraheem). Isaac married her and she gave birth to a set of twins, Esau (Al Eis) and Jacob (Yaqub).
Ill feelings developed between the two brothers when they grew into manhood. Esau disliked the fact that Jacob was favoured by his father and by Allah with prophethood. This ill feeling became so serious that Esau threatened to kill his brother. Fearing for his life, Jacob fled the country.
The People of the Book said that when Isaac was forty years old, he married Rebekah Bint Bethuel, during his father's life. They said she was sterile, so Isaac prayed to Allah and then she became pregnant. She gave birth to twin boys. The first one was called Esau whom the Arabs called Al-Eis. He became the father of Rum. The second one was called Jacob, which means Israel, (belonging to the people of Israel).
Jacob came to his father Isaac and settled with him in the village of Hebron which lies in the land of Canaan where Ibraheem had lived. Then Isaac fell ill and died when he was one hundred eighty years old. His sons Esau and Jacob buried him with his father Ibraheem Al Khalil in a cave which he had bought. It was said that Ibraheem died at the age of one hundred seventy five.
According to the Shariah of Ibraheem (AS), a man was allowed to marry two sisters, but according to the Shariah of Prophet Muhammadﷺ, you are not allowed to marry two sisters at the same time.
So Jacob (AS) agreed and married Rachel. When Jacob (AS) married the two sisters, Laban gave them a gift each. The gift was a slave girl each.
Leah's slave girl was called Zilpah. Rachel's slave girl was called Bilha.
Even though Leah was not beautiful, Allah blessed her with many kids.
All this time, Rachel did not give birth to any kids, as she was barren until this time. So because of this, she was jealous of her sister. So Rachel gave her slave-girl Bilha to Jacob.
Bilha gave birth to two sons Naphtali and Dan.
When Leah saw Jacob impregnated Bilha, she also gave her slave-girl Zilpa to Jacob. so Jacob ended up with four wives. Two wives and two slave girls.
He impregnated the slave-girl Zilpa and she gave birth to Gad and Asher.
So Rachel prayed to Allah and begged Allah to remove the obstacles preventing her from getting pregnant. So Allah accepted her dua and gave her Joseph (Yusuf) and Benjamin.
In those days, a man was able to go to sleep with his slave-girls and it was not considered zinaa.
And those who guard their chastity (i.e. private parts, from illegal sexual acts) Except from their wives or (the captives and slaves) that their right hands possess, for then, they are free from blame; But whoever seeks beyond that, then those are the transgressors; Quran Surah Al-Mu'minun 23:5-7
ALLAH KNOWS BEST
Stories of the prophets by Ibn kathir