You need to get the assessments not only for you and your family but her too. You don't say if all the children are in care or not, but then you have no need to

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Speak to your GP, your health visitor and ask for referrals for her. Prove she has something wrong.
After what I have been hearing on the TV I would avoid Social workers at all costs and go straight to my Health Visitor for help. Unfortunately they are already involved so get them to organise assessments of behaviour.
For court they need proof of neglect and abuse, I don't know if they have or have not got that, but a Judge won't just take Social Services word for it. However I feel the burden of proof lies with you and you need to gather evidence that you have not done what you have been accused off.
Maybe someone with legal knowledge will come along and help you...I take it you have a solicitor?
I am a single mum with twins, one who may have higher functioning autism. It not easy, especially when my boys teacher is making noises that I am an unfit parent and my son is just badly behaved

I have done Nursery Nursing training, so you can understand why I get so mad at this!