why do decaesed people open eyes at the time of ghusul

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

According to the known opinion of the scholars, the deceased person’s eyes remain wide open and their gaze remains fixed after their death; so it is an act of the Sunnah to close the dead person’s eyes after the soul departs the body. Umm Salamah reported that the Messenger of Allaah, sallallaahu ‘alayhi wa sallam, said: "When the soul is taken away, the sight follows it." [Muslim]

Shaddaad ibn Aws narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said: “If you are present when someone has died, then close their eyes, for the sight follows the soul. And say good things, for the Angels say ‘Ameen’ to what the family of the deceased says.” [Ahmad - Al-Albaani graded it Hasan (good)]

For more benefit, please refer to Fatwa 16905.

We do not know if it is possible for the deceased person to open his eyes after death or not; we believe that this is not possible because only the living person can open his eyes. The eyes and all body parts do not move unless the person is alive.

Allaah Knows best.