The Khai family consisted of Human individuals who belonged to the Lost Tribe of Sith found on the planet of Kesh. They were the descendants of those who survived the Omen's crash on the planet around 5000 BBY. This affluent family produced at least three generations of Sith, including Thallis Khai, his son Gavar Khai, and Gavar's daughter, Vestara Khai. However, Lahka Khai, Gavar's wife, lacked any Force-sensitive abilities.
Thallis Khai, a male Human, was a member of the Lost Tribe of Sith residing on the planet Kesh. He and the other members of the Tribe were all descended from the survivors of the crash of the Sith starship called Omen, which occurred on the planet in 5000 BBY.
Thallis had at least one son, Gavar Khai, a Sith Saber. Gavar married Lahka Khai, a woman who was not Force-sensitive, and they had a daughter in 27.5 ABY. Their daughter, Vestara Khai, became an apprentice to Lady Olaris Rhea after being the first individual on Kesh to be addressed by Ship, a Sith Meditation Sphere. She went on to serve in the Tribe's Sith armada, and she was the only survivor of the strike team dispatched to ambush Jedi Grand Master Luke Skywalker in 43 ABY. In 44 ABY, Gavar and Vestara Khai both participated in a fragile alliance between the Tribe and the Skywalkers for a mission aimed at defeating the dark side entity known as Abeloth.
The mission failed, and Abeloth escaped. Vestara Khai continued traveling with the Skywalkers as they pursued Abeloth, while her father advanced in rank within the Sith armada, eventually commanding his own flagship. Abeloth later allied herself with Gavar and the Sith on Kesh, only to betray them and destroy their capital city, Tahv. Lahka Khai was among the casualties, but Gavar, having fallen under Abeloth's influence, joined her forces. Abeloth dispatched Gavar and other Sith Sabers to ambush the Skywalkers, and they confronted the Jedi on the planet Dromund Kaas. Vestara remained allied with the Jedi during the duel, and she engaged her father in lightsaber combat. She ultimately defeated and killed him, which led to her decision to become a Jedi and begin a relationship with Jedi Knight Ben Skywalker.
