In "Tweenlight", when the families are done eating, there is still half of Flanders' body left. Homer asks a couple of questions and when we see the table again a couple of seconds later, the whole body is gone.
In "Tweenlight", Dracula mentions that when Lisa becomes a vampire she'll be immortal, so Edmund is too since his father said "you'll both be eight forever". However he later says to Homer that he remembered Edmund from a baby, sleeping in the daytime and checking he was still not breathing. How then can Edmund be a vampire from a baby if a vampire doesn't age?