fighting kitties

Hi, we have 2 sisters who have gotten along beautifully, we've had them since about 8 weeks old. This morning we were jolted awake by the sound of a cat fight in our basement (where they sleep)... and they've been angry and stalking each other ever since.

They've never done this before, just the normal kitty wrestling and aerobics...

Now one has a scratch in her ear and the other one is shaking her back foot and coughing (which she does when she is stressed). Nothing we can detect as far as what the fight was about...

Any ideas how to get them to be friends again?

Thanks,

Love in Christ,
Janie
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