I have 2 loving cats and they have been getting along for some time now. But as of today after several months of loving tender care towards each other they have become enemies. They look at each other like they're outsiders? They have been hissing and howling at each other. Why?! My bf says they saw another cat outside the window and that's when all hell broke loose! Now I have one in a different room and another in a 2nd room, what should I do why are they so freaked? How can two cats who spend all their time cuddling, licking, playing with each other become enemies? How is that mathematically possible? Please email to [email protected] I am new to this site and I do not yet know how to check mail. Thank you for reading my email.