Eva on the attack again...

Oh wow, what do I do w/ Ms. Eva??? She was doing so well not biting, but it seems she's back at it again. Brenda emailed me this afternoon saying, "Grace is good. Eva has bitten Jaidyn and Mollie today. They were playing with something and she wanted it. Mollie's left a welt on her leg but I'm not sure about Jaidyn's. She might have pulled away faster than Mollie so she didn't get it as bad. I sat her in time-out both times and she just cried. She bit Jaidyn first and then Mollie. I asked her if she wanted me to bite her and she said no and took off running crying. I told her if she bit someone again I was going to bite her back. She just buried her face in her hands and cried. I told her she had to sit in time-out for 5 min. After about 2 she looked at Grace and wanted her to get her. Grace said no Eva that is bad, you can't bite. You hurt Mollie."

I just don't know what to do w/ her - how can Grace be so sweet and Eva, well let's just say not so much??? And she'd so dang cute, she gets upset every time she bites someone and you correct her but doesn't seem to phase her.