Question:
hi there, right ive got 2 kittens, brother and sister, anyway i got the male castrated yesterday and when i got him home the sister wont let him near her, spitting and stuff, she never done this before , any ideas??

Answer:
This happens sometimes,your little male,coming back from the vet,now has a different smell than what he had before,one she does not recognize.
It will pass after a couple of days.
Cats know each other by smell,more often than sight

Answer:
Chico2 is right!

You can help matters along by rubbing both of them with the same towel.

Answer:
thanks very much

Answer:
You can also mist both of them with a light spray of 1 part vinegar to 30 parts water. It's recommended when adding a new cat into the mix. Something I recently learned and we've seen it be quite effective.

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