Copied from another thread I just posted on - forgive me for not typing it all out again.

Okay, here's my regular advice,

3 days is very early days - give it at least a couple of weeks before you see improvement. As I regualarily say on here - my parents had 2 that fought like mad for 6 months !!!! And are now best buddies. And when I say fought I mean fur flying, teeth and blood.

Try a feliway diffuser too.

Give it time and patience - it will get there. These things always take time, at least a few days if not a few weeks! Cats that just get on with a new stranger coming into their territory are very very few and very very weird!

Try scent transferal (i'm going to copy and paste now from another thread I answered, so forgive me . .

'I would invest in a feliway diffuser and set that going (it takes a few days to begin to work) it releases happy pheromones into the atmosphere and chills cats out, also try Bachs rescue remedy in their water. Then start scent sharing, rub all the cats with a towel - under their chins, base of the tail, their pads and rub this scent all over the house, on the walls, on the furniture etc, overlay the scents so they can all smell each other. Do this again but transfer the scent on to the other cats so they smell of each other, swap blankets over so they effectively sleep on each others scent. Then gradually supervise introductions - there is a good page on this website Welcome to the UKRCC too long to type out again but really worth a read about introducing cats to each other. Keep all this going for a while and they should eventually settle, also show your (gentle) disapproval of any aggression so it isn't acceptable in the house '

I'd walk away when your tabby hisses and growls, with a short 'stop it silly' or 'shht'. Once she is quiet come back. Bad behaviour equals no attention. Also I'd make sure that it is the kitten who is introduced into the house as the tabby was there first - so keep the kitten in the smaller area and allow the tabby to roam around. If this can be done where the kitten can see that your tabby is the priviledged one she will assume she is the alpha female and should act accordingly.

Your kitten shouldn't just be on milk at its age (not cows milk either most cats have an intolerance to the lactose in it and it can cause the runs) it is ready for proper food so let it have it.

Just imagine how you would feel if a stranger invaded your house and you were expected to immediately be best friends - it is very unlikley to happen! The cats need time to work out who is boss etc. A bit of hissing and bashing with a paw is all very normal and will soon ease off. It's just a warning and putting the kitten in it's place. I'd leave them to get on with it personaly, every time you remove the kitten from the situation the tabby believes she has chased the intruder away and therefore 'won', but the darned thing keeps coming back and soneeds chasing off again! SHe is just protecting you. Get them to play together too.

Try all of this and give it at least another couple of weeks. Eventually you will wonder what you were ever worried about. Good luck.

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