Qualifying child
A qualifying child of a taxpayer shall not be taken into account under subsection (a)(2) unless—
(i)#
the taxpayer includes the valid identification number of such taxpayer (or, in the case of a joint return, the valid identification number of at least 1 spouse) on the return of tax for the taxable year, and
(ii)#
the valid identification number of such qualifying child is included on the return of tax for the taxable year.