No Birthday Party?

Last week Liza started biting PJ. HOLY CRAP!! What's that all about? I told her if she did it again, she would loose her birthday party. This sounds very familiar. It happened last year, and she didn't get to have a friend party. I still let her have the family party, but this year I upped the anti. A few days go by, and low and behold, I catch her with her teeth in PJ's leg. No party. I decide to let her earn it back. Thursday and Friday, I make her work her butt off to earn it back. Finally, tell her she can have the party. Not an hour later, she friggen bites her brother- AGAIN!! Grr. I yell. I scream. She knows she is not having a party now. Not with friends. Not with family. What happens Saturday afternoon? She freakin bites him, AGAIN!!! According to Liza, each time he has deserved it. Thursday, they were playing in a box, PJ was climbing in with her. Chomp. Friday, they were watching TV and he didn't want to watch the same show she wanted. Chomp. Saturday, he put the crayons in the dogs' water bowl. Chomp. I swear the whole neighborhood heard me scream "He didn't deserve to be bitten! You don't get to decide what punishment he gets! You don't get to punish your brother!!!!" I am livid. So now, there is no TV, no friends, no spa night, and no birthday. We were planning to go to the zoo this morning with friends. Nope. Couldn't happen because Liza will not stop biting her brother. I am at my wit's end. I have had it. Only 10 days before school starts, and I already can't wait.