My daughter gone to live with dad hes taking me to court for full custody?

My daughter is only 10 and has had very little contact with her dad until recently,after a family row with her elder brothers and myself she decided she wanted to live with her dad,of course ss got involved and where against it because of his violent past but said as i had pr it was my choice after much soul searching my husband and i decided to let her go so she couldnt throw it back at me in years to come.I have had no contact with her since she went as the only number i have is his mobile i have a fab lawyer who is looking at court to hve her returned as he has no pr,he sent me some pr papers from 300 miles away and wanted me to sign them and send them back to him,as i was fully aware both parents have to be present at same time to do this,i told him so he said fine ill go for custody sorry he said we(him and girlfriend)he has been harring me for my lawyers add to the extent that she told me to give him it to get him off my back.can anybody relate to this any advice welcome