Your client doesn't have a tax problem.  Conceivably, she has a family-court problem if the other parent wants reimbursement for the $2,800 that now reduces his refund.  (Or does it?  The ACTC might have to be paid back, but not the RRC, right?)  I would focus on the client's tax return and not on someone else's tax return or on the shortcomings of federal government policy.