My suggestion is this, you need to rub towel, the one who is hissing or growling, all over the body. Once you do that, rub the towel to the other cat. With the same scent, they know they do belong in one pack.
My cat was 14 years old and was diagnose on 05/11/2015 with enlarge spleen (blood test and X-ray), platelet count is very low. The vet showed me the X-ray, how large was my cat spleen and had cancer. He lost so much weight, and gum was almost white (per vet the gum is not a good sign, "his in...
