I can tell you she was definitley not playing. Her ears where back and she was actively trying to attack him (I guess lucky for Charlie she has few teeth and no front claws). Charlie is the most submissive cat ever, I am pretty sure that he has never even tried to pick a fight with Sydney because he knows that she will kick his but. She has attacked him twice before, but it was because I ran after Charlie because he went outside to where my feral cat lives (who would definitley tear him to shreads). After chasing him back into the house, I really feel that Sydney thought he hurt me, because she ran in front of me and preceded to "protect" me. She is so cute when she sees that I have gotten angry, because she will place herself between me and the person I may be raising my voice at and she will precede to scream at us to stop. If you don't stop, she will give you a warning nibble in the calf that she doesnt like fighting. She is the best mediator ever! Back to this incident, I was just talking in normal tone on the phone - no yelling or anything. Maybe you guys are right and she was just letting me know that she is still the queen...