Sayyiduna Shaddad bin Aws (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: "When you are present with your dying, close their eyes, for the sight follows the soul, and say good things, for 'Amin' is said to whatever the people of the household say."
Hadith Referenceالمعجم الكبير للطبراني / باب الشين / 7137