What do Bella and Edward discuss concerning the killing spree in Seattle?

Bella reads an article about the escalating killing spree in Seattle. When Bella questions Edward about it, he tells her that they think it is the product of a growing group of newborn vampires. Bella worries about the behavior of the newborns in part because of the killings and in part because she worries that she will behave in much the same fashion when she is first changed into a vampire.