回複：parent as dependent for tax purpose. Please advise

Yes, you have to applied TIN

taxpayer is entitled to an exemption deduction for each dependent. A dependent means a qualifying child or a qualifying relative, with separate tests for each category. Pre-2005 law provided five tests for determining whether a person qualified as a dependent. Under both current and pre-2005 law, no exemption is allowed with respect to an individual unless the return claiming the exemption includes the individual's taxpayer identification number (TIN).