When Jeff killed his parents and tried to kill Liu, Liu survived and woke up in the hospital, a nurse explained what happened calling his brother a monster, that's when Sully starts telling Liu to kill her, Liu and Sully end up burning the hospital down. Since then they have been looking and tracking Jeff down, not to kill him but get his little brother back. (Liu is 18 and Jeff is 16) If you want more of this story just ask I will write more but it's no longer on my schedule