Hi can anyone please help ?,..my 4 year old daughter has a Undiagnosed neuroligcal problem with ataxia.

All doctors we have seen don't seem to no what there dealing with. She's had mri's,.. Ct's. lumber puncture nothing is showing. Her gait is so unsteady she is always falling ,.her speech is also badly affected. Lexi also does do jerky movements and her arm often wanders in the air. Can anyone please help me. Up until November lexi was progressing great like any other child of her age,. She is now deteriorating day by day