15.—(1) Subject to the following provisions of this regulation a person shall be treated as responsible for a child or young person for whom he has primary responsibility.
(2) Where a child or young person spends equal amounts of time in different households, or where there is a question as to who has primary responsibility for him, the child or young person shall be treated for the purposes of paragraph (1) as being the primary responsibility of—
(a)the person who is receiving child benefit in respect of him; or
(b)if there is no such person—
(i)where only one claim for child benefit has been made in respect of him, the person who made that claim; or
(ii)in any other case the person who has the primary responsibility for him.
(3) Where regulation 16(6) (circumstances in which a person is to be treated as being or not being a member of the household) applies in respect of a child or young person, that child or young person shall be treated as the responsibility of the claimant for that part of the week for which he is under that regulation treated as being a member of the claimant's household.
(4) Except where paragraph (3) applies, for the purposes of these Regulations a child or young person shall be treated as the responsibility of only one person in any benefit week and any person other than the one treated as responsible for the child or young person under this regulation shall be treated as not so responsible.