We have 6 cats and introduced an older rescue cat a few months ago. They all were fine at the time we were looking after my daughter's cat who didn't like the new cat and stalked her and bullied her. That xat has gone, but now a couple of oqur younger cats are doing the same thing. We have spray, we have Feliway, but they seem to have something against her.
Weirdly they sometimes lie together and are ok, but do then resort to hounding her.
Have you any advice. The younger cats are 14 months and 2 years. The new cat is over 3.
Can you give any advice?