What would happen if a zombie eats a zombie?

If a zombie were to eat another zombie, it would likely have little to no effect, as both creatures are typically depicted as already being dead and devoid of life. In many fictional portrayals, Zombies do not gain additional sustenance or power from consuming their own kind. Instead, it might simply serve as a display of mindless behavior, consistent with their instinctual drive to consume flesh. Ultimately, the scenario would depend on the specific rules of the zombie universe in question.