NC

We've had custody since 7-05 and complete physical and legal custody of our 2 grand daughters since 12-05. Given to us by DSS because of the parents' drug habits, frequenting crack houses, and their failure to care for the 2 children.
In 1-06, the mother joined the US Army and started paying child support of $300 every month. It almost pays the daycare bill. That's it.. She was deployed 11-06 - 11-07. We did not receive any more financial help although she got a huge bonus. Altho she is a soldier, she's still no more than an absent parent to us and the children, she has other priorities. She's stationed 3,000 miles from us, but still won't even call on any steady basis. She is about to be deployed again in February and we still get the same $300 a month.
Can we petition any dept for the allotment(s) that the mother would get had she been a responsible soldier/parent? If so, who would we contact to start with?
Thank you, anyone, for any help.