Hello, I have two 11 year old dogs and now a 2 month old puppy. My problem is that after the puppy drinks from the water bowl, the two older dogs refuse to drink the water until it is dumped and freshened, as if the puppy has cooties. The new puppy is up to date on shots and worming. Why won't they drink after the puppy or is there a way to rectify this? Will they eventually get over it?