Our cat, ironically named Mercy, grew up with our three dogs. When Fury died last year Mercy was heartbroken. Two days ago we brought home a new female puppy. Mercy approached, stopped before she could see the puppy in my husband’s arms, and began a two day tirade of hissing and growling. Mercy loves Havoc and Chaos–both large, playful dogs. Why does she hate the puppy without even interacting? Banshee is 1/3 Mercy’s size and we can’t have them in the same room for fear Mercy will kill her. I get that puppies can be annoying to cats, but Mercy hates her based on scent alone. We have been trying to reassure her with attention and often pet her after holding Banshee to positively reinforce the puppy’s scent. What else might help?