In 1995 Glasgow couple Darren and Frances Jenkinson suffered a terrible tragedy when their 2 month-old son Aaron died of a rare congenital heart defect. Or at least that's what the post-mortem concluded.Four years later, after undergoing fertility treatment, Darren and Frances managed to conceive again. But aged just 3 weeks, second son Jacob died in exactly the same circumstances.Suspicious hospital staff alerted the police to this unlikely coincidence, and detectives then unearthed disturbing signs that Darren might be responsible. He was a hypochondriac, had a penchant for setting fires and a desire to be the sole object of his wife's affection.In a chilling confession Jenkinson eventually admitted suffocating both his sons, under the direction of the voice of his dead father.