“that one of the parents of the child or qualifying young person is dead and the person claiming a guardian’s allowance shows that he was at the date of the death unaware of, and has failed after all reasonable efforts to discover, the whereabouts of the other parent;”
“In the case of a decision relating to child benefit or guardian’s allowance, the making of an appeal under this section against the decision as originally made must follow the Commissioners for Her Majesty’s Revenue and Customs first deciding, on an application made for revision of that decision under section 9, not to revise that decision.”