I spied on you when you were bathing
Zhai Tianyu has never doubted the death of his aunt because of how careful the person was behind it, while he was investigating the cause of his aunt's death, not once did he find any traces of any second person behind it. From the landslide to the corpse of his aunt, everything was taken care of rather well.
In this world, there was no such thing as an autopsy of a human body and even if there was one, the physicians here wouldn't be able to differentiate the stab of a knife that was later replaced by a small piece of wooden plank, but Jia Li who was used to seeing a different kind of stabs was able to differentiate it with just one glance, she even told Liu Hui Ying the length and the width of the blade that might have been used in the assassination of Zhai Chenguang.