Larg was added to The Doctor's program by B'Elanna Torres in an effort to make the picture-perfect family more real. He subsequently forbade his son to see either Larg or K'Kath and suggested that Jeffrey would find some nice Vulcan friends. However, the ban was lifted by Charlene, who questioned The Doctor's new family rules in schedules.
In this modified version, Larg, along with K'Kath, supplied Jeffrey with a kut'luch, with which the Human boy was supposed to kill an innocent person in order to prepare himself for his future life as a warrior. The Doctor did not approve of this ritual, and told the two Klingons to leave. (VOY: "Real Life")