Kestra Troi (2329-2336) was the first child of Lwaxana Troi and Ian Andrew Troi. Being half Human, half Betazoid, it was unclear whether she would develop full telepathic abilities or only empathic ones. She died from drowning in Lake El-Nar on Betazed at the age of six, several months after the birth of her younger sister Deanna Troi.
After her death, her mother had a bizarre reaction to her grief, and attempted to wipe the girl's existence from her memory. Her father Ian accepted this for a time but planned to confront her in 2343. However, he died before he could do so. Lwaxana subsequently fired her valet, Mr. Xelo, for keeping some evidence of Kestra's life. (TLE novel: The Art of the Impossible)