Former best friends fighting

Question
Hi Ali,  I have 2 cats (not related), a male & female who had been best friends.  The male is older and was adopted first and took a very maternal role with his new sister.  About six weeks ago they got into a fight (one jumped in front of the other and startled each other, resulting in hissing, howling, scratching/swiping at each other) and have not been the same since.  There are moments when they seem to get along, but it's more "tolerance" than the love they once had.  I don't know what to do anymore.  It is breaking my heart to see them like this and I can't bear the thought of having to get rid of one.  I've tried keeping them apart, ignoring them, yelling at them, interactive play, everything and nothing is bringing a permanent solution.  The best result I had so far is where I ignored them.  They seemed back to normal the next day (chasing each other, curled up sleeping together purring) but since then they've fought at least once every day.  Do you have any advice?

Thank you,
Heather

Answer
Heather,

I would strongly suggest that both cats have a complete physical exam including blood and urine work ups to rule out any medical problems with either cat. If one cat is sick and the other recognises a different scent coming from them then you could be seeing a cat trying to communicate that he/she doesn't want the sick kitty around. This is something that I have seen occasionally, recently my oldest cat was diagnosed with kidney issues and before we knew that she was ill my two younger cats were hissing and generally harassing her, we only found out when she became obviously ill. If you have the cats both examined and nothing medical shows up my other guesses would be along the lines of seeing wildlife or another house pet through a window or door that has upset or frightened one or both cats, there is also a possibility that there have been recent changes prior to when the fighting started that have upset them. I would suggest that you begin "treating" this problem by investigating the cause, is there a sound, smell, sight, etc that triggers outbursts? For instance does the garbage truck put the engine brake on near your house (this would create a loud rumble, remniscent of a really loud growl in the eyes of your cats)? Are there large trucks stopping nearby using air brake mechanisms (which hiss loudly)? Has the neighbor's dog or cat been coming and marking their territory on your lawn? It almost sounds to me like the aggression you are describing is frustration/anxiety based. If the problem is something that the cats are seeing outside you can try purchasing a removable frosted window covering which still allows light in, but prevents the cats from seeing the object of their frustration. If there is a loud noise that is the source of the problem which could be anything I have described above or even as simple as kids making a lot of noise coming home from school, a car backfiring...Sometimes it only takes one time for a circumstance to occur and frighten or aggitate the cat so that they take out fear based aggression or frustration out on each other. In either case I recommend that you start your cats on a homeopathic remedy called Bach's Rescue Remedy, which is a collection of flower essences designed to treat trauma, anxiety, aggitation...You can usually purchase the Rescue Remedy at health food/natural health stores. The dosage I would recommend of Rescue Remedy would be 6-8 drops in fresh water every morning. I have seen dramatic improvements in short periods of time. You may find that the Rescue Remedy won't completely solve the issue, if things get worse I would stop using it right away. I have never had behavior like you describe get worse with Rescue Remedy, but if it does or the Rescue Remedy just plain doesn't help at all then you may have to discuss anti-anxiety medications with your vet for one or both of your cats, but approach this with caution as these medications are not without side effects. I hope that I was able to at least offer some insight. If you have any further questions or concerns, please do not hesitate to contact me again.