Best friends now hate each other

[FIFIBEBE]

Wondered if anybody had any bright ideas? We have 2 beautiful 4 year old spayed sisters. Both cats stay indoors and get along really well. One cat spent the night outside a week ago (didn't realise she had got out). On her return all hell has broken loose. The cat who was left indoors has attacked the one that got out many times, hissing, tales up and other signs of aggression. The one that got out has become timid and is spraying and has pooed in a few locations. I assumed it was related to smell but thought it would wear off after a few days. Any help appreciated. TIA

Anyone??

I don't know, unless she had a Tom around her and the other one can smell it.

One of ours would come home stinking of Tom even though she was neutered.

You could seperate them, swap bedding over for a few days and slowly build up to a reintroduction.

That's all I can come up with.

Thanks, they are separated, well different rooms and avoiding each other. Have swapped their towels and feeding separately. They have just had a low level growl so perhaps things will improve over time.

I would think so - and I agree with Fluffy about building up to reintroduction as if they were stranger cats. Which they're not of course. They may have had a bad week but they're not starting from Point 1.

Feliway, not that I know much about it, but sounds like a textbook case when it should help.

Thank you lljkk, I will get some tomorrow.