Diabetes is a disease that affects how the body uses glucose a sugar that is the body's main source of fuel. When you eat, Glucose from the food gets into your bloodstream, your pancreas makes a hormone called insulin, which helps the glucose get into the body's cells, and your body gets the energy it needs. Diabetes can affect any age, she might be having Type1 diabetes which is known to occur in early age also. She needs proper treatment and continuous follow up. Death is not due to diabetes but due to complications resulting from uncontrolled states. So make sure that sugars are well controlled.