Replies to 'Pre-school'

I have a problem that maybe some of you pre-school moms and dads could give me advice on. I have a 4 1/2 yr old little girl. She has never really had a problem at school until recently.  After Easter break last week I took my daughter back to school, she was happy to go back, but I thought I'd see some tears, because during Xmas break she started to cry a bit but no big deal. I expected the same after the Easter week off but all went well until I got a call from school about an hour in. I go to get her, and she seemed to be over whatever was bothering her. The teacher said she started to cry went into the corner and was asking for her bear. So I decided to leave her in class but stayed because she only had maybe 30 mins or so left. I figured seperation issues. She goes to school Mon. Wed. and Fri. and she had "meltdowns" those days as well..but not as bad. I finally got out of her that a kid in class was sitting somewhere he wasn't supposed to be and she apparently told him to go away but he didn't. That is all that she would tell me. Anyways today after a nice weekend and talking to her I took her back  to school and as soon as this kids car pulled in next to ours she went off the walls yelling and screaming sayings he wanted this kid to go away. I told the teachers and I told them to keep this child away from mine, but my daughter will not tell me what if anything happened other than him sitting on the chair next to hers. When I told the teachers all of this the teacher said she did notice that when this child was acting out in class on Friday that she was getting upset. Other than keeping my child away from this other kid I have no idea what to think or do! Any advice anyone?!?! She was fine all up until Easter and the whole week she was home..but something has it the fan so to speak and I' at a loss here. Sorry for the ramble but I need a venting and some suggestions/advice