child on child abuse - what do I do to make them listen?

[iamatiredmum]

Hi - I wonder if anyone can help as I feel like I"m going mad. I have four children, three of whom are disabled. The youngest is autistic and seven and a child in need in the complex disabilities team. He is incredibly violent and I think enacts child on child abuse on his nearest sibling, who is a girl and aged nine. She is also autistic.

In the last month alone, he has stamped on her head, threatened her with a knife and pulled her along the ground by her hair (several times). But my efforts to get her supported by social care have come to nothing. I keep being told that we have to see if her early help worker's involvement will provide sufficient support before they review her needs.

I have formally submitted an assessment of needs request for her, and also a revised carers' assessment for the whole family (she is a young carer) back in February to the LA and haven't even had a response.

I rang the duty social care team to report the child on child abuse and was just told that I need to pick this up with her brother's social worker. But I have raised it with them and they keep telling me she doesn't meet the threshold for an assessment.

ARGGGHHH - feel like I'm losing my mind.