From running, to limping, to crawling, now won't walk

I am a preschool teacher and I have a child that both me and the parent is concerned about. The child went home okay for the weekend.  But over the weekend, her nmom noticed she was walking funny and just assumed she had fallen.  She took her to the ER and the doctors gave her x-rays and couldn't find anything.  She went to get opinions from two other doctors this week and still no one see's anything wrong.  The parent has not mentioned any blood work  just x-rays and doctor evaluations.

On monday the child was running some, walking some normal, and limping a bit, sometimes crawling.  but once she started to crawl she appeared to be in a lot of pain.  The next day she waslimping more and walking less.  And Friday, she wouldn't move from the spot or position we placed her in and occasionally seemed to be a bit distached until we were somehow able to grab her attention.  I didn't mention the bit of distatchment to the mother because I didn't want her to be any more concerned than she already was. Oh yeh when she limps, she leans to her left with her ear nearly touching her shoulder.  neither heel touches the ground, but hte right heel remains higher off the ground than the left, assuming more pressure is put on the left foot.

Does ANYONE have any idea of what is going on with this baby?.  It hurts us all to see her in pain and not functioning normally.





Other side info:
She is eating normally, she doesn't have as many teeth as the others in the class.  SHe only has 2 front bottom teeth and is breaking two bottom molars. She seems to be urinating less.