Throughout his life as a theologian, Christian minister and cosmologist, Prof David Wilkinson has been asking - what does God do when I pray? The question became acutely personal after his wife, Alison, developed first ME and then crippling rheumatoid arthritis. As everyone prayed for her recovery, but no healing appeared to come for many years, the couple and their children felt their faith come into sharp focus. For their children, now both working for the Church, there was a profound crisis of faith which left them unable to pray. For David, anger and confusion that his wife, also a minister of a growing church, was left in pain and unable to walk, let alone lead her church. Naomi Wellings meets a family whose faith was shaken, but ultimately strengthened.