I can understand why Jacob (or smokey) would appear as Walt to Locke ( they had a connection, both said they didn't want to leave the island, they were happy there) but appearing to the dog as Christian makes no sense, the dog never met Christian, it would make more sense for him to be Walt or Walt's step dad or mom, wouldn't it? Or was this just intended to be a very deliberate ohhhhh moment? Please discuss amongst yourselves.