yellow cat grumpy

We have two barn cats- about 18 months old. They are brother and sister. Have always been close and played together until recently. Now the female (a orange tabby)has gotten really grumpy with her brother- if he even goes near her, she hisses and won't let him come near. They used to sleep together but she won't let him in their bed anymore. She seems very healthy. Any thoughts on what is going on here?

Answer by Kate
Hi
Are both the cats neutered/spayed? IF not then this is most certainly the reason.
Even though they are brother and sister te cat hormones and scents ake over and to your female cat he is just another male cat. She may also be in heat and this too can change her behavior towards other cats.

IF they are neutered then it could smply be plain old territory scables and again their relationship to each other would count for very little if territory is an issue.

If your acts are not spayed or neutered I would urge you to get both done as soon as possible. This will not only prevent unwanted pregnancies but will also make your cats calmer happier cats without all the fruststrations associated with mating etc.

best wishes kate

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