Who is Leah from Waiting for Anya and what is their importance?

Leah is a young Jewish girl who has been sent to Madame Horcada's farm so that Benjamin might help her cross the border. The child is very young and she becomes quite attached to Benjamin. Unfortunately, Leah becomes so attached to Benjamin that she refuses to go into Spain with the other children at the end of the book. Leah is caught with Benjamin on that fateful night and also dies in a concentration camp.