Littermates have gone from mutual grooming to hissing

Hello,

I been reading many posts across many forums but haven't found a truly similar issue. I have two 5 year olds males, fixed. They are grooming buddies and usually sleep together during the days and lay around with me after playing. One cat is larger than the other but the smaller cat has alway been first to eat and is generally more dominant than the larger.

About two weeks ago, the three of us were sitting together and playing. My larger cat nipped the smaller in the tail which is normally met with little slap at most but it triggered war. Hissing and swatting, no grasp and bite. Separating them in my home is very difficult as there is no place for a second letterbox, food and water. I did separate them over two days, spending a few hours with one and then the other.

On day three I took the smaller of the two to the vet for a check up. He had been listless prior. He had some consitpation and she expressed the anal gland. Upon returning home from the vet the two curled up together and were back to normal for a week.

Last night, the larger cat was demanding attention but I needed to run an errand. When I returned about 2 hours later they had started back up with the same behaviors. I'm sure that the larger cat took his frustration with me leaving out on his buddy and the smaller cat is afraid or angry at him again. I returned to the vet and she gave me some Feliway spray. This calmed both cats down but they still are intolerant of each other.

I really want to keep our family together but I'm not sure how to get them to play nice again.

Cats will often act out when one of the other cats is ill or has been to the vet.  The cat you took to the vet smelled differently from being ill and then when it came home from the vet, it had so many new and different smells attached to it.  Many people will put a small drop of vanilla extract on a cotton ball and rub it over each cat after a vet visit.  This allows the cats to smell the same.  You can also take a washcloth and rub down the cat who did not go to the vet. You want to be sure to get the scent glands, so under the chin and paws.  Then take the washcloth and after the vet visit rub down the cat who went to the vet.  It will have a familiar scent to it. 

Here are a couple of articles to read

http://www.catbehaviorassociates.com/aggression-between-cats-after-a-veterinary-visit/

http://www.vetstreet.com/care/nonrecognition-aggression-in-cats

The feliway spray might take a bit to work.  You might want to get a diffuser as well.    This has a calming effect on cats.  Also Composure liquid or treats might help them as well.

Thanks for your reply. The aggression did happen because of the vet visit... Actually it helped. When I returned from the vet they slept with one another almost immediately. This isn't nonrecognition, this seems more like a dominance or territory issue.

The problem re-appeared after a week of peace and love between the two and I think that I caused the aggressive behavior when I left the without giving the larger cat the attention he was seeking.

With the defusers... When normal, like to hang out in the living room together and my bedroom and will often eat together.... Do I need 3 of them or will one cover a house?

The diffusers will only cover a certain amount of space.  If you have a small home and the cats hang out in only one general area, then one should be enough.  I always have one in every area the cats hang out it, but found the spray to be very useful in small areas too.

Look into Composure feline treats or Composure liquid max.  It is a non sedating supplement that calms cats.  I have used it for almost 2 years on my cats.  I prefer the liquid as it is easily mixed into wet food and some cats don't like the treats.  You can find it on Amazon.

Thanks for that advise.

I'm tempted to allow them to work this out on their own. It doesn't seem as though they'll hurt each other. It's usually just a two foot stand off with mutual hissing and yowling. Is that a better solution than refereeing with pot lids?

The larger cats starting to show some submissive behaviors but he gets defensive when rebuffed. Which brings up another question; I've been allowing the smaller cat to hang out with me. He's the one that's starting the hissing and yowling. The larger usually responds by freezing and starring back at him. Am I hangin out with the wrong cat? Given that the larger one caused the initial aggression but the smaller one persists. I've have been giving them larger some alone time with me when I can confirm that one or the other has eaten. Intentionally getting as much scent on me as possible.

I should start using their names. The smaller white kitty is Mandu aka Du. The larger is named Atonic aka Husker.

Thanks again for all of your advice thus far it's much appreciated. I'm being long winded in the posts in the hopes that someone might pick up some detail in the dynamic that help solve this.

Bob

 Hello, Bob! Your kitties are beautiful & I hope that you can get this worked out soon! I have found that community playtime often helps.  I use a  long teaser (homemade ones using old fishing poles or lungewhips for horses are great) and stand in the center,  gather the cats around and have them take turns at the teaser. I have had brothers & sisters fight as much as brothers & brothers. For one particularly stubborn brother, I take him for sunset/sunrise walks (I live in a rural area and we have to climb a cliff in our backyard to access our tablelands), calling him by name. the other kitties follow, of course, but it seems to give him the confidence/self-importance that makes him tolerant of the others. this is what I had to do for my Maine Coon - I think some kitties have a very high energy level that will diffuse itself either in lots of play and exercise, or lots of tormenting their siblings.   I am sure that your situation started innocently enough, with the original nip unexpectedly hurting the smaller cat due to his medical issue & the smaller cat justifiably reacting to that pain in a way that startled and angered the bigger cat. Please keep us updated on what you find works for your crew because this is a common issue and we have a many guests surfing here who will benefit from your knowledge gained during these experiences   Prayers and vibes! Susan

Thanks Cats. They aren't much for play but I've been using my "cat fishing rod" and laser as a redirect behavior. If I've got them sequestered we play to exhaustion. Luckily I can pick up either of the in full out hissing mode and they don't bite me. So I've been just grabbing the closest one and putting them both in time out separately for a 1/2 hour. Then letting Atonic out so he can have some time unharrassed. Once Atonic settles in, I let Du out. And repeat. Not being scientific about it but I think the time they are tolerating each other is getting longer and the aggression is one sided and not as nasty.

So Cats... The question is do I keep up the interventions or just let them do their thing and this too shall pass?

Seems that an armistice has been reached. I'd bet this method will work for any situation where you've got aggression.

Go see a vet and make sure that the behavior isn't related to health problems.

The secret was to remember is that once the aggression starts your part is over until everyone's calmed back down. Don't intervene unless there's biting, then make a loud noise with something, like pot lids. I'm forever impressed with Du's 4ft vertical.

Boredom seems to be the cause of most aggression in multicat households. I'd been lax on the play for a few weeks and I'd bet that all this could have been avoided if I'd taken the time to play with my buddies. Use a string toy or anything that will give you some distance to play. I've got a string tease toy which gives me about a 4 foot circle where I control the action. Get them both interested and playing. Let them both get a kill or two in. Then start leading them closer and closer but give room to make an attack without getting too close to the other guy. This process blew up on me a couple of times. Keep it up until you can get them close or touching each other. Any interaction that you get through without any aggression no matter how small should be rewarded with praise.

I used Feliway in a "choke" point in the house where they would have to pass close to each other. I plan on terminating the Feliway now that we've got things back to normal.

Don't think you can go back to ignoring them. Go buy some new toys to maintain the interest level and look for any opportunity to play.

Thanks to all who chimed in and provided advice.

 Adorable pic - I am very glad that harmony has returned to your household!! Thank you for posting what has worked for you!! You are an excellent cat guardian