If a Paladin were to be turned into a sentient Undead, most make you automatically evil. In this case it is Vampire; now in my mind when you become a vampire, you are more or less possessed by a dark spirit, or at least you psyche is changed in some way but you can still be redeemed. (If you were brought back to life, you would be back to the old you).
Now, if you become a Vampire as a Paladin, do you Automatically become an Anti-Paladin if your alignment is Chaotic Evil? I am just curious if the change would be more automatic.