Grow up

My coworker is still giving me the silent treatment. I'll admit that I do act immature more often than not, but even I can tell that this is beyond immature behavior. Yesterday, she threw her designs on my desk so I could check them. Today, she transferred a call to me without telling me who it was or without telling the caller she was going to transfer her. Granted, the caller is someone the designer hates, but still, there's no reason to be so rude on the phone. What did I do? I decided to be extra nice and bubbly to the caller. Passive/aggressive behavior. Isn't it the best?