Yes, Abram and Sarai were related. They were half-siblings, sharing the same father but having different mothers.
No, Sarai was not Abram's sister. She was his wife.
Sarai was Abram's half sister.
Abram
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Sarai is the wife of Abram. After Abram made a covenant with GOD, GOD changed his name to Abraham. His wife was no longer Sarai, but Sarah. She is the Mother of nations, not the Bible. For the Bible was not written yet. It would not get its first book for another 500 years or so.
God changed Abram's name to Abraham and Sarai's name to Sarah as a sign of their new identities and the covenant He made with them. It symbolized their transformation and the promises God had for them.
Sarai's name is first mentioned in Genesis 11:29-31. Sarai is believed to mean: Princess. The Lord changed her name to Sarah (princess of nations). At the same time the Lord changed Abram's name (exalted father) to Abraham( father of many nations) See Geneses 17:5,15. Sarai was Abram's brothers daughter, Haran, who died. She and Lot where adopted by Abram's father, Terah. When Abram travelled to Egypt with Sarai, his wife at that time, he did not lie when he told the Egyptians that she was his sister. Technically she was, being the adopted daughter of his father.>
Abram was married to Sarai who couldn't have children. She had a servant called Hagar and because Sarai was so desperate for children she told Abram to sleep with Hagar and if Hagar got pregnant, she would have the baby and then Abram and Sarai would raise it as their own. Abram agreed and Hagar got pregnant. Hagar began to hate Sarai and Sarai was upset and said that God should judge whether Sarai or Abram was right or wrong. Abram told her that Hagar was her servant and she should do what she wanted with her. Sarai was horrible to Hagar and Hagar ran away. While Hagar was running away, she saw an angel who aksed her what she was doing and she told the angel that she was running away from Sarai. The angel told her to go back to Sarai. The angel also told her to name the child Ishmael and that no-one would like him.
According to the bible in Genesis 12:5 Abram had a wife named "Sarai"
Sarah; originally Sarai (Genesis ch.11 and 17).
This is hard to explain. The Book of Genesis says that God gave Sarai the new name, Sarah, when he gave Abram the new name of Abraham. However, Sarai and Sarah have the same meaning in Hebrew, both meaning 'Princess'.
According to Genesis 12:13, Abram feared that the king would kill him in order to have sex with his wife. Abram somehow knew that the king would not kill her brother for the same reason, so told the king that she was only his sister. For the same reason, he successfully deceived the king of Gerar by saying that his by now quite elderly wife really was his sister.