When Yoichi's mother is killed, the blood coming from her body is very obviously just colored water, as it is too bright and too thin to really look like blood.
This film is actually the second sequel to "Ringu." The first sequel, "Rasen" was shot back-to-back with "Ringu" with a different crew and director, and some of the original cast. It was then released simultaneously in theaters alongside "Ringu", in hopes that fans of "Ringu" would go to see it. After "Rasen" failed with both critics and audiences, the director of "Ringu" (Hideo Nakata) was re-hired with the original screenwriter and the original cast to film this "alternative" sequel which is written as though "Rasen" never happened. This film want on to be a success, while "Rasen" became the "lost sequel."