thats such a difficult situation, my prayers are certainly with you. My cousin had a child that she repeatedly neglected (no bathing, no table food at a year, etc) to the point that the child was severly physically,(crawled at 18 months, walked at 2 1/2) socially, mentally, speech delayed, etc. CPS was called on numerous occassions, by dr's, by her relatives, by neighbors, but no action was taken until the child was put into direct danger (she left him alone in a car, overnight, in a bad neighborhood, while she did drugs in a house) My aunt went through numerous battles, first she registered as a foster parent so that when CPS DID take him, she would be eligible to have him (they did place him with her) then after a year, she went to court to petition for custody (denied, even though the mother had at that point made no attempts to fix the situation or follow CPS's instructions on parenting classes, etc and was in and out of jail for drug charges) When the mother finally DID follow through with certain requirements CPS immediately removed him from my aunts home (where he was just catching up, with the help of physical, occupational and speech therapy services!) and again, she had him taken away. This has been ongoing for nearly 7 years now.
When my aunt has him, he excells, when he's with his mother, he declines and regresses, and the state laws are so set to side with the parent that, IMHO, the child is the one that is sacrificed.
my prayers are with your family!