The trauma undergone by Kate and Gerry McCann during the last 13 years since their little daughter Madeleine disappeared from their holiday apartment in Portugal is beyond the imagination of most of us, and every parent's nightmare.
ot only did the couple have to live their lives in the glare of worldwide publicity, they also had to contend with absolutely unfounded allegations that they were somehow involved in their daughter's disappearance.
Today they have new hope that the mystery of Madeleine disappearance may at last be solved. German prosecutors have named a man in custody as a person of interest and are investigating him on suspicion of having murdered the little girl.
However, Jim Gamble, a highly experienced former RUC officer who went on to specialise in tackling child exploitation cases, agrees with the McCann family that their daughter could still be alive.
He regards this latest development as the most encouraging news he has heard in the last 13 years and that view will have carried weight with those who believe this case could be solved soon.
Everyone hopes that Madeleine is still alive in spite of the German prosecutors' decision to treat this as a murder inquiry. The evidence against the man in prison, from what has been made public, appears to be circumstantial and it is vital that anyone who was in the Praia da Luz resort on or around May 3, 2007 looks out for old photographs or video recordings in case they could include a vital clue which could help the prosecutors.
We in Northern Ireland have had many cases of people who disappeared without trace, including Lisa Dorrian, Arlene Arkinson, Capt Robert Nairac and Columba McVeigh, and in every case their families have continued to live with the misery of not knowing exactly what happened to them or where their bodies are.
They, like the McCann family, would give anything to gain closure. To have a loved one snatched away and never see them again is one of the most traumatic experiences anyone could suffer.
In the McCanns' case, there have been countless theories put forward which have all proved to be groundless. But perhaps Jim Gamble's optimism that this could be the vital breakthrough will prove true. Certainly the man in the German prison cell should cooperate fully with the authorities to either disprove their case or else bring closure.