Parliamentary Voting System and Constituencies Bill

If the Government get their way, the referendum will take place on 5 May 2011, so based on the logic of her case surely the hon. Lady should be arguing that people who are 14 next year, who will be entitled to vote at the general election on 7 May 2015, should also be enfranchised. That is the logical conclusion of her argument, so why is that not the amendment she has tabled?