Complex sentence: However, in order to stay in power, Trevor's brother, Oren Goodchild, had her killed along with the other members of the experimental group, and ordered all of Trevor's research to be destroyed.
Split into simpler sentences: However, in order to stay in power, Trevor's brother, Oren Goodchild, had her killed along with the other members of the experimental group. He ordered all of Trevor's research to be destroyed.