At one point in her life Kahlest was the object of affection of K'mpec, but she refused his advances because she found him "too fat".
When Mogh suspected a plot against the Khitomer outpost, she went with the family in 2346 and tended to Worf during the visit. Mogh and his wife were killed during the attack on Khitomer while Kahlest was with Worf. She survived the attack severely injured and was transported by the USS Intrepid to the biomedical facility at Starbase 24 for treatment. During this time she allowed Worf to be adopted by Sergey Rozhenko, a Starfleet non-commissioned officer serving on the Intrepid. The massacre had greatly affected her, and she considered herself "dead" as her House was now gone.
In 2366, when Mogh was dishonored by being declared the traitor of the Massacre, Worf came to challenge the Klingon High Council. As his cha'DIch, Jean-Luc Picard came to Kahlest to get her testimony of the events. She initially refused, but changed her mind when she saw Picard's bravery as he was attacked outside her door. He killed one of the assassins and she killed the other. She then accompanied Picard to the Council chambers, but was told by K'mpec that her statement would not be needed. K'mpec commented it was good to see her again, upon which she replied that he was "still fat". (TNG: "Sins of the Father")