Cats growling at each other

[1fortheisland]

I have two cats, Paris and Florence. They are 8 months old and are siblings. Both are females and both have been spayed.
They've been having some tummy troubles (diarrhea), so I took them to the vet today. The vet gave them a clean bill of health. This was their first visit to the vet since I got them (in December). They were both very scared in the vet's office, but the visit was short and the vet gave them a clean bill of health. I brought them home and things were fine until just now.
Florence has been growling and hissing at Paris. Florence will hide herself under furniture or behind objects, and will growl at Paris every time Paris comes near her or gets within her line of sight. Paris has been keeping her distance, but she seems upset and wants to play with her sister. Florence growls and hisses every time she sees Paris - she has never done this before!
I'm not sure what to do. I'm keeping them separated, but it's hard because our apartment is so small. I'm worried that this will become worse, and I don't know what I will do tomorrow when I have to go to work and can't be home to monitor them.
Does anyone have suggestions?

 

[vball91]

This could be a case of the vet office smell although it does not happen as often when both cats go to the vet together. Florence may not recognize Paris' scent. You can try wiping them both with a little vanilla extract, or try rubbing one down with a towel and then the other to mingle their scents. If it is a case of the vet smell, it should wear off soon.

 

[1fortheisland]

They've been home together for several hours, but Florence's aggression didn't start until recently (about 45-60 mins ago). I'm mostly worried because it's after midnight where I am and I need to get some sleep. I've put Paris in the bathroom, but she is crying incessantly, and it's driving me a little crazy.

 

[catwoman707]

Just as vball said, it's the vet smells, you can also take a dryer sheet and rub it along both of them, then they will smell like each other and the vet smell will fade.