A day ago my 2 year old Siamese female cat was sitting in the window she always does, a stray female approached the window and my cat got very aggressive and started meowing and hissing very loud, with all of her fur standing up. Other cats have been in the window with her before and she never reacted this way. I managed to get her away from the window and closed it, but when I put her down onto the floor she immediately went after my other cat (8 years old, also female). My Siamese has grown up with my older cat and they have never had a problem, always been close (clean each other, sleep with each other).
So far I’ve had them separated all day, given them both treats and sat with my Siamese to try and calm her down. Every time I leave the room she is in she freaks out again. I also rubbed a towel on my older cat and put it in with the Siamese so she could get used to her scent again.
Any other suggestions on what I can do to help her go back to normal? I’m also 8 months pregnant and I’m terrified she will get like this with a new baby in the house. Do you think so?