4-month-old Hissing At Littermate?

[Evie's Mom]

Hi all!

So this spring we had a feral mama (Toulouse, extremely skittish, took us months to earn her trust) have kittens in our house. 3 of them, two boys and a girl. Two (Starmie and Arlo) have since gone to good homes, about two months ago, when they turned 8 weeks. The last (Winston) had his home fall through and is staying with us while we search.

Anyway, Arlo is our guest for the week since his new mom is out of town, and he is so sweet - playful, cuddly, kind to the other cats. Winston and Toulouse however are a different story! Toulouse wants nothing to do with her son and has hissed and swatted at him. She is currently being kept separate. Winston is downright mean to Arlo! Hissing, growling, spitting, swatting - the whole nine yards! They haven't even been apart for two months, and Arlo's new mom was going to foster Winston for a while, so his behavior is extremely distressing.

We did give Winston (since he is the smaller one and we figured he was being defensive) his space for a bit but he continues to show this behavior. We have tried distracting them with treats, food, and toys, but every time Arlo tries to play with his brother, Winston hisses at him! We have been spraying Winston with water every time he hisses, but he does it again. We have been giving Winston extra love and affection away from Arlo, thinking he might be jealous, but it doesn't deter him.

The strange thing is that, about three weeks ago, Arlo came over to get his claw grinding. They were fine then, even playing. What could be causing this, and how do we stop it?

 

[danteshuman]

I wouldn't interfere with hissing. It is cat speak for 'this is my territory' or 'stay away from me'. Hissing does not necessary lead to attacks. I would keep an eye on them when they interact though. I'm also not sure about using the squirt bottle to correct hissing. I find it much more effective to distract the cats with toys to take their aggression out on or to separate them temporarily for a short period of time. (I usually kick the aggressive one out for 3-5 minutes or move the picked on one to more secure location .... like one of his favorite high places to be.) Another thing you can try is using a large piece of cardboard to separate them with so they can't see each other. (3 feet by 3 feet should do it.)

 

[Evie's Mom]

They're able to be calm for a few minutes at a time but I'm worried about the swatting and fighting (they've gotten into tussles a couple of times now, even supervised, and I'm worried about someone getting hurt. We're keeping them separated unless they can be supervised.

 

[danteshuman]

Are they bleeding? Fur being ripped out? Making those horrid cat yowl sounds? That happens from true fights. Heck my 2 boys live with another cat and one time that cat put a tiny very light scratch on the muzzle of my grey cat. Right above his nose. It was the only time blood has been drawn. They all get along (though they occasionally annoy each other.) Since he is going to be gone in a week it might be easier to just keep them separate.

 

[Columbine]

I agree that keeping Winston and Arlo separate for now is the best solution. Cats don't often take well to having other cats as houseguests, even if they're littermates. I suspect that something has happened in the intervening three weeks to change Arlo's scent. It could be something as simple as a vet visit, especially if that visit involved neutering. Cats recognise each other by smell more than sight, so a scent change could well mean that Winston no longer recognises Arlo. If they were going to be living together long term, I'd be thinking in terms of carrying out cat-to-cat introductions, just like you would if you brought in a stranger-cat from, say, a shelter. The same process might benefit Toulouse's and Winston's relationship too (though in their case the hostility could just as easily be down to mom having had enough of her babies and wanting some peace and space!). The most important thing is to minimise everybody's stress levels and to make sure that all are safe.
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