Janess

Janess Idaho is a fictional character from the "Dune" universe created by Frank Herbert. She is the second eldest daughter of Murbella and Duncan Idaho, born a few minutes after her twin sister Rinya.

Janess and Rinya are rare exceptions to the Bene Gesserit rule that daughters must not know their true parents. Murbella chooses to disclose her identity to them because she feels that of her children, these two had the most promising talents.

In "Hunters of Dune", Janess and Rinya are prodigies, ambitious, impatient, and unquestionably talented, but Janess possesses just a hint more caution. Janess is obsessed with learning more about her father Duncan Idaho, and she often quotes his philosophical works. Rinya always has to be first for everything, and thus she demands to be allowed to undergo the spice agony, wanting to become a Reverend Mother at the age of fourteen, just like Sheeana had done. During the ritual, Janess rushes forward and cries out that her sister isn't ready for the test, that Rinya herself told her so. She attempts to stop the proctors from inserting the poison but is blocked by Bellonda. Rinya fails and dies, Murbella not knowing whether Janess's prescience had foreseen it, or if she had caused it.

Janess swears she will only undergo the agony when she is certain she is ready. Her time arrives at age 17, and she becomes a Reverend Mother without any problems. Murbella gives her the rank of Lieutenant, and her first assignment is to clean out a renegade Honored Matres group who controlled a portion of Gammu. Janess suggests to her mother that a small groundforce be sent to strike fear into them, but Murbella insists that the Matres can never be trusted back into the New Sisterhood. Janess agrees, suggesting they be exterminated like insects, and Murbella orders it. Janess is later promoted to Regimental Commandant, and adopts her father's last name.