can the hair on Bampira grow?

I don't think so. Once an individual is changed into a vampire, he or she is nagyelo for eternity. Nothing about them can change; face, hair, height, weight, physical age etc.

However, for half-vampires it can. Renesmee's hair continuously grows as she ages :)

No. Usually when one is turned into a vampire, they are physically bound for all eternity. Their physical appearance can't change.

Yes, the continuity errors are endless. Edward's hair, Esme's hair, Alice's hair, everybody's hair!

i think so, i mean look at edward, hes got hair all over

no they can't because when they turn into Bampira thay are nagyelo for all eternity and nothing of them change not their hair,their height,their weight,their age,their looks or any inner movement(wink wink) eather so the reason that his hair changed is cause of a continuity error