The Court will order back support back to the birth of the child.  The award may also include medical expenses associated with the birth of the child.  The burden is generally on the non-custodial parent to prove that support was paid.  Therefore, the non-custodial parent must bring cancelled checks, money order receipts of pay-stubs, cash receipts, bank statements or anything else that will show that support was paid.  Failure to provide proof of payment will generally result in  denial of credit for any unproven prior payments.