- "She drove me to it. May the curse of all the Powers rest upon her for ever."
- ―Jadis, speaking of her sister. (Chapter 5) [src]
Jadis' sister was born a princess in the world of Charn. Little is known of her, not even her name.
This princess was probably the younger of the two. She was known to be a clever witch, just as her sister was, though not as powerful as Jadis.
After Jadis' ascension to the throne, the princess chose to challenge her in a power struggle. Both sides agreed to a use of no magic, and proceeded to go to war. Jadis claimed that her sister broke the promise that neither of them would use magic, but there's no way to verify this. Jadis was hardly trustworthy, yet it is known that all of Jadis' family and race were said to be cruel people. So Jadis' sister may have been just as bad as she was.
In spite of Jadis' advantages, her sister's armies had the upper hand in the last battles. Fighting in the great city of Charn itself, the two armies butchered one another until the princess and her officers were able to reach the royal palace where Jadis was stationed.
"Victory" was the princess' last word, spoken to Jadis. Even as she and her forces overwhelmed Jadis', her elder sister also chose to break their pact, and call on the power of the Deplorable Word to destroy not only her enemies, but all her own forces as well. Within minutes of entering the palace, the princess and all the armies had died. Jadis was left the empress and sole living resident of the whole world of Charn.