What was the name of Cleopatra's sister who led a revolt against her?

Cleopatra’s sister who led a revolt against her was Arsinoe IV. During the Alexandrian War of 48–47 BC, Arsinoe escaped the royal palace and joined forces opposing Cleopatra and Julius Caesar. She was proclaimed queen alongside her brother Ptolemy XIII and became a symbolic focus for resistance inside Alexandria.

Arsinoe’s forces helped conduct the siege against Caesar’s troops, and ancient accounts portray her as taking an active leadership role with the military commander Achillas. Although the revolt initially threatened Caesar, Roman reinforcements eventually defeated the Egyptian army. Arsinoe was captured and taken to Rome, where she was paraded in Caesar’s triumph in 46 BC.

Caesar spared her life and sent her into exile at the Temple of Artemis in Ephesus. Cleopatra continued to regard her as a political danger. In 41 BC, Mark Antony ordered Arsinoe’s execution at Cleopatra’s request, an act that violated the sanctuary’s protection and caused outrage in Rome and Ephesus. Arsinoe is sometimes confused with Berenice IV, another Ptolemaic princess who had earlier challenged Cleopatra’s father.