Concept art for Twilight Princess implied that the Kokori eventually became the inhabitants of Ordon Village. Rather than become Koroks, they became proper humans. Illia and her father in particular shared characteristics with Saria and the Deku tree respectively.
In the moment of attachment for the death of the Hero's Shade, I just imagined that it would be nice if Saria and Navi came to pick him up.If Saria and Navi are real or simply an illusion, i'll leave to your own consideration.
