LAHORE - A six-year-old girl was killed while her sister and mother were injured when a roof collapsed on Mohni Road near Data Darbar here on Wednesday.  The police said that the woman with her two daughters were sitting in the room when the roof caved in.  On information, teams of Rescue 1122 reached the spot and pulled out them from the debris while Rania Kashif died on-the-spot while eight-year-old Sania and their mother were shifted to the Mayo Hospital.