These are the rules from 6th April 2012:
Lone Parents
Lone parents with at least one dependant child, who is working 16 hours or more a week.
Couples with children:
Couples with at least one dependant child, and
- one of the couple is working 24 hours or more a week or,
- both are working a total of 24 hours or more a week as long as one of them is working 16 hours or more a week, or
- one of the couple is working 16 hours or more a week, and the other is 'incapacitated', in hospital or in prison, or
- at least one of the couple are working 16 hours or more a week, and either of them are entitled to Carers Allowance.