48 Hours - 17x16 - Prime Suspect: Billy Fox- Followmy.tv

Billy Fox, 33, is a devoted father of two and a soccer coach. He appears to be an all-around regular guy from Wichita Falls, Texas, with full custody of his children, Skylar and James. But now, he's about to turn himself into the police, as they book him for the death of a baby. It's a charge that could put him in prison for the rest of his life. "What attracted me so much to Billy is what a wonderful father he was," says Billy's girlfriend, Cassie Herring, who first met Billy in 2000 -- just a few years after his divorce. At the time, Cassie was raising two children of her own: Peyton was 2 and Cameron was a newborn. In a matter of months, they all were under one roof. But in less than six months, startling events would shatter this new family. Correspondent Susan Spencer reports.