Massacre on Tehar

In 34 ABY, the First Order military, under the command of Kylo Ren, committed a genocide against the population of the Unknown Regions planet Tehar. Afterwards, the only survivors were two young siblings, Kel and Eila, who escaped by stowing away on a starship. When the First Order learned there were survivors who could tell others about the atrocity, they set out to hunt down the two children.

Behind the scenes
The genocide of Tehar was first mentioned in the Star Wars Resistance episode "The Children from Tehar".