Over the last few weeks Persil has developed the habit of picking fights with Dushka. I have had to separate them several times, pick Persil up and give her time out in a bedroom. The silly thing is that Dushka is bigger than Persil, and naturally defends herself, so that it is Persil who comes off worst. She has had several bites and scratches on her face and neck, one of which only just missed her eye. I can find no reason for this behaviour - she play fights with the others but it doesn't turn nasty, and she is her usual self towards me, more loving if anything. Why would she be jealous of Dushka, certainly nothing has changed in the house? It is always Persil who starts it, she ambushes Dushka, stalks her and chases her until Dushka turns and growls, then it is fur flying all over the place.