(a) For the purposes of this section, '''qualifying child'', in relation to a claimant and a year of assessment, has the same meaning as in section 462, and the question of whether a child is a qualifying child shall be determined on the same basis as it would be for the purposes of section 462, and subsections (4), (5)(b) and (6) of that section shall apply accordingly.
(b) This section shall apply to an individual other than an individual referred to in paragraph (a) of the definition of ''specified amount'' in section 461(1).
(2) Subject to subsection (3), where a claimant, being an individual to whom this section applies, proves for a year of assessment that a qualifying child is resident with him or her for the whole or part of the year, the claimant shall be entitled -
(a) if he or she is a widowed person, to a deduction of £2,650, or
(b) if he or she is an individual other than a widowed person, to a deduction of £3,150,
but this section shall not apply for any year o