Stephen Clark's fight for his granddaughter: The battle against spinal muscular atrophy (SMA)

Spinal muscular atrophy (SMA) is the number one genetic killer of children. There is no cure, no treatment and very little public awareness of the disease. 7 Action News anchor Stephen Clark is out to change that. He’s on a very personal mission to save his young granddaughter, Scarlet, who suffers from SMA.