Although they have a sibling love hate relationship apart from an occasional swipe they've never fought.
Over the last few weeks a strange cat has appeared and it's driving them crazy. Full blown fights with each other and Snorg has a notch missing from her ear. The visiting cat just sits by the door. And they go mad. Yowling, hissing, fur flying. They've never had an issue with cats I've brought into the house for fostering. Although they've all been Persians.
I've put the pet remedy diffuser back on. Felipe at doesn't work for them. Anything else I can do to try and calm it down. I try to block their view with the curtains.