Kessynna was one of the daughters of King Haedrak II, known as the "Corsair Prince", of the Lions' Dynasty. The manner of her death is not recorded, but she passed away some time before 1274 DR, and she had five surviving daughters.
Sometime in 1274, these five daughters and three of their aunts, Kessynna's sisters Cyralna, Chynnil, and Pyriiss, traveled to Waterdeep, because Cyralna was married to a noble of Waterdeep, Ortaal Emveolstone, and their first child was due. After a month in Waterdeep, Cyralna and her newborn child died in labor. Shortly thereafter, all seven princesses were murdered in their sleep by mimic grubs disguised as pillows.
Within a tenday, it was discovered that the two responsible were Kyvan Emveolstone, Cyralna's brother-in-law, and Prince Toram, Cyralna and Kessynna's own brother. When Cyralna's father, King Haedrak, heard the news, he dropped dead. The new king, Cyralna and Kessynna's other brother Errilam I, ordered the execution of the two murderers, and they were drawn and quartered in Waterdeep.
Before the truth about Kyvan and Toram came forward, the Knights of the Shield began spreading rumors that the Harpers were responsible. Even though Kyvan and Toram had no connection to the Harpers, Harpers have not been welcome in Tethyr since 1274 DR because of these tragic events.