It's took place over a decade ago, but the story of Madeleine McCann's sudden disappearance from a resort in Portugal during a family vacation continues to baffle and haunt many people.
Over the last 11 years, there have been many leads, theories, and clues about the three-year-old girl's whereabouts, but the mystery remains unsolved.
Madeleine's parents, Kate and Gerry McCann, recently gave a rare interview in which they discussed the night their daughter vanished, and despite being told to give up hope, Gerry still believes Madeleine will return one day.
The detectives on the case aren't as optimistic about Madeleine, who would now be 15, being found alive, but they have recently claimed that they're "closer to the truth" about her abduction.
Earlier this year, authorities revealed that they have identified another suspect. The mysterious "woman in purple", according to a couple of witnesses, was standing outside the Ocean Club apartment where the little girl was allegedly abducted from just 90 minutes before she was reported missing.
She has since been identified as Luisa Todorov, a 58-year-old waitress, who worked at at a nearby restaurant, was "acting bizarrely" and "watching intently" after the abduction. The Scotland Yard and Metropolitan Police, who took over the case from the Portuguese police, have been following the lead, but are unable to share the details of the ongoing investigation.
So far, over $15 million has been spent on the case, which has been dubbed Operation Grange. In March, over $200,000 was pumped into the investigation to help the investigate an "important final line of inquiry."
The last funding period was set to expire in September, but the detectives have just been granted another $250,000 to continue their investigation for at least the next six months.
For Madeleine's family and their supporters, this new development is a sign that the police may be closer than ever to solving the case. However, there are some individuals who think the additional funding is a waste of money.
Karen Downes, the mother of another missing child has recently told The Sun that the extra focus the police have placed on Madeleine's case means that her daughter and other missing children "are being forgotten."
"I feel very angry that other children - Charlene and so many others - are being forgotten," said Karen, whose daughter Charlene went missing in 2003. "A child goes missing in the UK every three minutes. What about all those others who never come home again?"
She added, "If they are going to plough money into the search for Madeleine, then they should do the same for all the children who are missing."
The devastated mother questioned why Madeleine's case has gotten so much attention while her daughter's didn't.
"It was during the trial that Madeleine McCann went missing and it was plastered all over the newspapers and the TV. It was a global story. I was devastated for her parents. But I also wondered why Charlene's disappearance hadn't had the same attention. If we'd had that kind of coverage, maybe she would have been found, before it was too late. I will never know. It just doesn't seem fair on my Charlene."
There are also a few experts who agree with Downes on the funding issue, but for a different reason.
Crime expert Pat Brown previously told news.com.au that the government should stop funding the investigation because "Madeleine is dead."
"There's no point spending all of this money as nothing they do is going to make that child alive," she added. Brown also claimed that Madeleine was not kidnapped, but rather, she died "of an accident occurring through neglect and possible medication."
Brown's theory was also echoed by former detective Goncalo Amaral in his controversial book The Truth of the Lie. In it, he alleged that Madeleine had "died and her abduction was a "cover-up."
At the end of the day, these are all theories that aren't backed up by any proof, so we'll just have to wait and see what the police ends up finding.