TORONTO Twins are a handful to raise but when you have the burden of a life-threatening illness added, it becomes a real struggle. That’s what a Maple, Ont. family is dealing with as their twin daughters, Stephanie and Tiffany, face a debilitating illness known as Spinal Muscular Atrophy or SMA. “They just sit only 15 seconds and they fall over easily and they cannot move even their toys,” says Noryoulay Chhuon, father of the 29-month-old girls. Last summer the girls were diagnosed with SMA Type 2 and they began a series of painful spinal injections, every four months. The drug Spinraza can slow the disease’s progression but it doesn’t stop it. Eventually their mobility, their digestion and even their breathing will deteriorate. SMA often claims the lives of children before they reach the age of 2.