The production delayed for two years since 2011, was finally scheduled for April 2013 but the director had to advance and to start filming on January 2013 because the child actor, William O, was going to loos his first tooth, then the main photography started with the scene in the park to continue then on February 2013.
Another curious fact is that the scene of the suicide attempt was filmed in studio, but the director did not like the atmosphere in the studio and was shot again in the original location getting the realism required for the scene.