The development first came to light when a bookseller left a comment on theBookseller.com. It read: "We received stock of Jacqueline Wilson's new book Cookie at work today.
In a statement Random House said Wilson had agreed to the banding on the back of the hardback after "close discussion" with the author. The statement read: "Jacqueline can see the arguments both for and against printed age guidance on books but does retain some reservations about the subject. She has agreed for age guidance to be put on the cover of Cookie but RHCB will maintain the discussion with her and her agent over the matter and will review the situation on a book by book basis."