Can the doctrine of unclean hands, bar a litigant from a child support modification?

My ex (custodial) filed a petition to modify child support while the children were living with me (nc). Typical joint agreement. She and the children (twin boys) moved in with me in August, she was having money problems. I was the sole-provider for the needs of the children. Beginning of February she moved a half hour away, the children stayed with me. In March she filed a petition to modify the child support (increase), claiming income up, child's needs up, cost of living. There is undisputed proof the children resided with me, school records, doctor records, neighbors, etc. Should her petition be denied because the children did not reside with her at the time of her filing? Should a parent that is asking the courts for a modification for the children have the children?