The parents of Madeleine McCann have marked her fourth birthday with a fresh appeal for help, nine days after she went missing from a resort in Portugal.
Mr and Mrs McCann attended a local prayer vigil in the Algarve
In a statement, Gerry and Kate McCann asked people to "redouble their efforts" to help find their daughter.
Chancellor Gordon Brown said every parent would be thinking of the McCann family and what they could do to help.
Madeleine, of Rothley, Leicestershire, disappeared from an apartment in the resort of Praia da Luz on 3 May.
Huge sums of money are being offered to anyone who gives information leading to Madeleine's safe return.
A group of business people and celebrities, backed by the News of the World newspaper, have pledged a total of £1.5m in reward money.
Donors include Sir Richard Branson, Top Shop's Sir Philip Green and the paper itself, which has put up £250,000.
Their offer comes days after Scottish tycoon Stephen Winyard, owner of Stobo Castle in the Scottish Borders, offered a £1m reward.
Mr Winyard said he would be "rejoicing with the rest of the nation" if the reward helped to secure Madeleine's safe return.
On Saturday, in a statement read out by Alex Woolfall, a rep from holiday firm Mark Warner, the McCanns said: "Please keep looking, please keep praying, please help bring Madeleine home."
They spoke of the "huge amount" of effort being put into the search, and said offers of support were being made daily.
"It is this that keeps us strong and gives us hope," they said.
The girl's aunt, Philomena McCann, said the couple would be having a "family day" to celebrate Madeleine's birthday, and her life so far.
Other family members would be gathering at the Glasgow home of Madeleine's uncle, John McCann, she said.
"We want to have a celebration just now and have another one when Madeleine comes home - the sooner that is the better."
She said the celebrations would be small and would help to "galvanise" the family's union.
Meanwhile, players in Saturday's football match between Celtic and Aberdeen will wear yellow ribbons around their wrists to show their support.
And two Portuguese players for Edinburgh side Heart of Midlothian - Jose Goncalves and Bruno Aguiar - made an appeal for anyone with information to come forward.
Former England football captain David Beckham, who plays in Spain for Real Madrid, also made an appeal on Spanish TV urging her safe return.
There has been speculation that Madeleine could have been taken out of the country.
Cardiologist Mr McCann earlier said he and his wife, a GP, had seen at first-hand how strong the police's desire was to find Madeleine.
He said: "We will leave no stone unturned in the search for our daughter Madeleine."
The official ground search for Madeleine in the Algarve has ended, but police say they still have significant leads to follow up.
The focus is shifting from being a local search for Madeleine to an international child abduction inquiry.
Media reports about leads have focused on CCTV footage from a petrol station on the night of Madeleine's disappearance.
It was thought to feature two men and a woman driving a car with a British number plate.
Police have declined to confirm or deny reports about any possible leads, citing Portuguese law.
The UK's Child Exploitation and Online Protection Centre (CEOP), which works to tackle child sex abuse, has launched a poster campaign appealing for information on Madeleine's disappearance.
The international number for Crimestoppers is +44 1883 731 336. People with information about Madeleine can call anonymously.