movie identification help
 

I only remember bits and pieces of the movie but ill try to give as many details as I can. the creature seems to follow a certain bloodline/people and when one dies it goes after the other, its weakened by copper, they uses copper bullets I think from a police station, and I'm not to sure but I think the creatures name is Cain/Kane which ever spelling is correct. any help would be appreciated.

How old do you believe it is?

I'm not to certain how old it is but I believe it early 2000s or older
not within the last 10 years at least