You do know that these kids aren't professional ball boys don't you? They are kids from local grassroots football teams on the whole. They turn up an hour before kick off and get to borrow some "uniform", get a brief talk about what to do - which includes being told not to climb over the holdings or enter the field of play.
My son did it recently with his team. They all had a great experience which surely is what it is all about....
Not anymore I'm afraid. Mourinho knows