It is more, says Pietro Orlandi, than any family should have to endure. For almost three decades, the Orlandis have carried on hoping that Pietro's missing sister, Emanuela, who disappeared without trace aged 15 on a summer's day in Rome in 1983, will come back to them. Or, at least, that they will find out what happened to her. "All these years without any explanation is absurd," he says. "We have been waiting and waiting for an answer, but still it hasn't come."
This week has seen the latest twist in the heart-wrenching saga. On Monday, Italian police opened up the diamond-studded tomb of a murdered Italian gangster, Enrico de Pedis, in the crypt of the Basilica of Sant'Apollinaire, in the centre of Rome. They were acting on a tip-off made to Italian television's equivalent of Crimewatch, in which an anonymous caller suggested that the key to solving the mystery of Emanuela's fate lay in opening de Pedis's tomb. Unidentified bones have now been taken away for analysis. All the police will say, for sure, is that they are not from de Pedis's body.
Lurid allegations have always surrounded the Orlandis' ordeal. Emanuela's father, Ercole, was a lay official in the Vatican, working in the department that organises papal functions. Shortly after his daughter vanished on June 22, 1983, having attended her regular flute lesson, a series of telephone messages was received, linking her fate to that of Mehmet Ali Agca, the Turkish gunman who had attempted to assassinate Pope John Paul II in May 1981.
The callers said they were holding Emanuela, who had Vatican City citizenship, as a bargaining counter to force the authorities to release Ali Agca. The Pope himself became involved, making as many as eight public appeals for Emanuela's release, and visiting her family. But to no avail. The calls stopped and the trail went cold, though Agca subsequently claimed that Emanuela was alive and well in an enclosed convent in eastern Europe.
Since his father's death in 2004, Pietro Orlandi has continued the fight to find the truth. He isn't convinced that everyone in the Vatican shares the late pontiff's determination for his sister to be returned unharmed. So he has organised an online petition that has attracted 80,000 supporters in an appeal to the world headquarters of the Catholic Church finally to reveal everything it knows about the case.
"Many of the petition's signatories," he explains, "are faithful Catholics who are indignant about this situation and are asking the Church to make clear its position."
Those who have joined the chorus of criticism about the Vatican's lack of candour also include senior Italian officials. "There are still people alive, and inside the Vatican, who know the truth," the assistant prosecutor on the case, Giancarlo Capaldo, told Italian television last month.
And in a remarkable sermon, given on Good Friday in Saint Peter's to a congregation that included Benedict XVI himself, Franciscan Father Raniero Cantalamessa, a member of the papal household since 1980, spoke of "atrocious" crimes that had gone unsolved for years. "Don't carry your secret to the grave with you," he pleaded. Although Fr Cantalamessa did not refer to any particular case, his remarks were widely interpreted as part of the effort to put an end to the Orlandis' agony.
The initial Italian investigation into the girl's abduction rejected any link to Ali Agca in favour of the explanation that Emanuela had been lured away for sexual motives and then murdered. But another popular theory linked her with the banking scandal that engulfed the Vatican in the 1980s. Ercole Orlandi, it was suggested, had evidence of wrongdoing by Archbishop Paul Marcinkus, the controversial American prelate who ran the Vatican's bank. To keep Orlandi quiet, the story goes, Marcinkus, who died in 2006, arranged for the kidnap of Emanuela (possibly by de Pedis's gang, according to the gangster's former mistress).
The warmest lead in the case came as long ago as 2005, when an anonymous caller to the television programme Who Has Seen? alleged that Emanuela had been seized at the behest of Cardinal Ugo Poletti, Vicar-General of Rome, in 1983. The motive was, it was hinted, sexual - but since Cardinal Poletti died in 1997, he cannot defend himself. However, it was he who, in 1990, agreed to the burial of de Pedis in the Basilica of Sant'Apollinaire, an Opus Dei church usually reserved for the burial of senior clerics.
For seven years, the Vatican resisted opening up de Pedis's tomb. But this week's events at Sant'Apollinaire show that it has woken up to the damaging perception of its involvement in a cover-up.
Meanwhile, Pietro Orlandi faces yet another wait - this time, for forensic scientists to reach their verdict on the bones that were taken away for examination. He is encouraged that progress is finally being made towards "transparency and collaboration between the investigating authorities and the Vatican", but isn't holding out any great hope. His family's turmoil, it seems, knows no end.