Bring Teddy & Maddie home to their mummy

My two children, Teddy & Maddie, were taken by their father after I left the relationship due to abuse. He decided to take them from me and refuse to let me see my babies for 9 months. Maddie was 11 months old and Teddy was three. Finally, the court awarded me a night and an afternoon a week with my children. Not much, but to me it was everything. Two years on, he has decided to break the court order and take them again. It's been nearly six weeks since I've seen them, and the only reason why is because they've both said they want to live with mummy, Teddy was brave enough to ask, and was called a f**king little pr**k and his father said he never wanted to see him again. He changed his mind soon enough and said they didn't have a choice. I couldn't break the court order. They're being physically hurt by his new partners son and their father has put a lock on the outside of their bedroom door. He has called social services on me, saying I hadn't brushed Maddies hair. Social services said to me they thought it was out of spite. I have a brilliant solicitor & need a barrister, we have a fight on our hands as he has moved them away against my wishes, put them in schools I knew nothing about, I couldn't even tell you who my kids Dr is.
My heart is breaking. I miss my children so much, my ex is breaking the law, but all that really matters is the fact my kids hearts are breaking too. They need their mum. I am desperate for them.
I will do whatever it takes and never stop fighting.