Rebecca Clark was a colonist. She was the daughter of Quentin and Louise Clark. The Clark family were aboard the transport ship Incunabulum traveling to RLW 1289 when the vessel unknowingly set down on a moon infested by Xenomorphs, leading to the death of all but one of its crew and passengers.
Rebecca, along with the rest of the crew, was captured by the Xenomorphs and taken to their Hive. She was killed soon after entering the nest, when two Xenomorphs tore her apart while fighting over her body.
Rebecca was killed in the early stages of Church's experience within the hive, when two Xenomorphs began fighting over her and accidentally pulled her apart in the process.