My step daughter turned 18 in January. She is not in full time education. She doesn't work either. She claims benefits. She moved out of her mothers home last June when she was 17 to live with her boyfriend. However the CMS is saying my partner has to pay maintance from last June and to keep on paying it. Can anyone tell me if this is right? You still have to pay for a child over 18 and not living with either parent.