It's a very long story kassee, it started when they split up and he left her for another woman, he left her with huge rent arrears which resulted in her and the boys being evicted and made homeless, she sent the kids to live with him whilst she found a job and a home and he refused to give them back. She has had trouble finding a permanent home due to 2 unscrupulous landlords who took deposits and never handed over keys, because of the arrears on the first home she can't get on any waiting lists or get a reference. He however has a rented home and a girlfriend.
There are lots of times the judges side with dads, especially when mum can't afford legal representation but dad can.