The reason why the Third Prince died was not due to any conspiracy, but because his soul had been nurtured and was ready to leave his body and return to the Underworld to assume his duties.
In fact, when a Judge reincarnates, it's inherently troublesome. Comforting the spirits whose reincarnation opportunities were taken away is the easiest part; the real challenge is owing gratitude to the parents of the body after reincarnation.
Ghost Messengers and Wu Chang don't possess power as strong as that of a Judge, most can live a full lifetime, sending off their parents before passing away. However, a Judge's power is overwhelming, typically returning to the Underworld in two to three decades.
This means their mortal body is bound to die young, and the greatest sorrow is a white-haired person sending off a black-haired one. Therefore, after a Judge returns to the Underworld, they continue visiting the mortal world to support their body's parents until they grow old.
