if qualifying child claimed by another member of family (i) General rule Except as provided in clause (ii), in the case of 2 or more eligible individuals who may claim for such taxable year the same individual as a qualifying child, if such individual is claimed as a qualifying child by such an eligible individual, then any other such eligible individual who does not make such a claim of such child or of any other qualifying child may be considered an eligible individual without a qualifying child for purposes of the credit allowed under this section for such taxable year. (ii) Exception if qualifying child claimed by parent If an individual is claimed as a qualifying child for any taxable year by an eligible individual who is a parent of such child, then no other custodial parent of such child who does not make such a claim of such child may be considered an eligible individual without a qualifying child for purposes of the credit allowed under this section for such taxable year. . (2) Taxpayer eligible for credit for worker without qualifying child if qualifying children do not have valid social security number Subparagraph (F) of section 32(c)(1) of the Internal Revenue Code of 1986 is amended to read as follows: (F) Individuals who do not include tin, etc., of any qualifying child In the case of any eligible individual who has one or more qualifying children, if no qualifying child of such individual is taken into account under subsection (b) by reason of paragraph (3)(D), for purposes of the credit allowed under this section, such individual may be considered an eligible individual without a qualifying child. . (d) Effective dates The amendments made by this section shall apply to taxable years beginning after December 31, 2016.