Birthday Idea - Concertina Card

Although this was made for a friend who is seriously ill in hospital, it would work just as well as a novel Birthday Card/Book.
It is the usual construction of a concertina card with two single section books sewn in the front and back folded section.
I wanted to write a little greeting at the beginning and added a secret to the back section. Writing the whole thing in a long concertina would have spoiled the surprise.
Quite a twist on the usual construction.