The parents of abducted Madeleine McCann say they pray she is being cared for by someone who wanted a daughter of their own.
Kate and Gerry McCann are due to meet senior officials in Spain
Speaking in Spain, her father Gerry McCann said he hoped that whoever had taken her would leave her "at a church or a safe place".
The couple are in Madrid as part of a tour of several European countries to publicise Madeleine's case.
Earlier this week, they met Pope Benedict in the Vatican City.
The Pontiff blessed a photo of the missing four-year-old old.
Mr McCann and Madeleine's mother, Kate, are due to meet the UK ambassador to Spain, Denise Holt, and Spanish Interior Minister Alfredo Perez Rubalcaba.
Madeleine, from Rothley, Leics, vanished during a family holiday in Portugal on 3 May.
Mr McCann said the couple were "imploring" the people of Spain to help find her.
"When we think about it we pray that she is looked after and it is someone who wanted a little girl for their own who would look after her very well," he said.
"We also pray that the person who has her gives her up voluntarily and drops her at a church or a safe place."
The couple flew from Rome back to Portugal, where their two-year-old twins Sean and Amelie have been left in the care of Mr McCann's sister Trish Cameron and her husband Sandy.
After a brief stop-off, they took a flight from Lisbon to Madrid.
The couple want to raise the issue of child abduction generally, but also believe there is a chance that their daughter may have been taken into Spain by whoever abducted her.
Meanwhile, Spain has been preoccupied by its own case of child abduction: that of seven-year-old Yeremi Vargas, who disappeared in the Canary Islands two months ago.
The McCanns, both 38, appeared on a Spanish television programme called Los Mas Buscados - or Most Wanted - which appeals for help to find missing people.
As well as making their own plea, they were given a letter from the family of Yeremi Vargas.
'Not in isolation'
Speaking at a packed press conference, Mr McCann asked for "reassurance" from Spanish police that there had been "some proactive investigation" into his daughter's abduction.
He also referred to the Vargas case, adding: "I think it is at least worth exploring the possibility that Madeleine's disappearance should not be considered in isolation and in the context of other disappearances in the Iberian peninsula, even the Canary Isles as well.
"We do realise that there are other families in Spain who have had similar experiences, particularly the family of the young boy Yeremi from Gran Canaria.
"Our thoughts and prayers are with his family and with other families going through a similar experience to us."
Earlier, the couple met representatives from child welfare organisations, including the Associacion Contra la Pornogafia Infantil, an anti-paedophile group.
During their European mission, the McCanns are also due to visit the Netherlands, Morocco and Germany.
This week they released the last video clips taken of their daughter before her abduction.
And they have reiterated their appeal for information on Madeleine and urged people to visit their website, www.findmadeleine.com.