CNN  —  The bright pink jumper with a picture of Cinderella hangs off Jana’s skinny shoulders as she walks through the northern Gaza moonscape, piles of rubble, dirt and dust all around her. Clutching a large tub in her hand, the 12-year-old is on a mission: find food and water. Jana Mohammed Khalil Musleh Al-Skeifi and her family say she has been responsible for getting supplies for them all since an Israeli sniper killed her older brother more than a year ago. Her parents are in poor health,