Foster cat intimidating resident kits. Apologies in advance for the lengthy post... About 3 weeks ago I agreed to foster a friend's cat for an indefinite period of time. Friend moved into a houseshare and discovered that one of the housemates is horribly allergic. So Ariel, a 3yo black boy (neutered) came to live with me, my partner and our two 1yo sibling cats, Angus and Wanda. Angus & Wanda are very friendly, inquisitive cats. They're pretty easygoing. Ariel, not so much. Although we don't need to keep them separated anymore, they aren't quite friends yet. Ariel growls and hisses at them, and occasionally will swat at them if they come too close. Then other times he'll bump noses with them, only to hiss and growl a few seconds later. *I've witnessed some chasing from both camps but it's hard to tell whether it's aggression or play. Could it be a bit of both? What should i do when he hisses at them? Usually I try to distract him with a toy (which of course then Angus and Wanda want to play with too), or sometimes I make a loud noise, such as a hand clap or a loud NO!* I just don't want my two kits to feel displaced. They do seem to want to be friends with him. Angus more so than Wanda - if Ariel hisses or swats at Wanda, she'll sneak up behind him a few mins later and swat his tail. Sometimes they just seem uneasy around him, and I swear they give me the stinkeye when he crawls into my lap!! Also, Wanda sometimes hisses at Angus when they're playing, which she's never done before (they are usually inseparable). Ariel has just started going outside in the past couple of days (his owner let him out all the time but I keep mine in), which seems to relieve stress levels a bit. I've also got a Feliway plug-in and spray (he's spraying a bit as well, though the combo of Feliway + enzymatic cleaner has helped). They all happily feed together near each other, and I tend to give them treats together so they associate their presence with something positive. Am I going about this the right way?*Do you think it'll eventually calm down? My two are quite "alpha" personalities, but Ariel is definitely used to being top cat. It doesn't seem fair for my cats to be dominated by a newcomer!