Madeleine McCann's parents are making an impassioned plea for authorities to re-examine their investigation exactly three-and-a-half years after the British girl went missing on a family vacation in Portugal.
Madeleine's disappearance set off an international search in 2007, but when few clues emerged, the case went cold.
Now, "Early Show" co-anchor Erica Hill reports, Madeleine's parents are reaching out again for help. They recently spoke to British Sky TV asking for a new investigation into their little girl's disappearance.
Gerry McCann said in that interview, "Madeleine's a British citizen. She's innocent, she's vulnerable, and our government should be doing more to find her."
With an online petition, the McCanns are demanding a full review of the investigation by British and Portuguese authorities.
It was just days before Madeleine's fourth birthday when she disappeared from a Portuguese apartment building where the McCanns were staying. Parents Gerry and Kate had left their three children alone while they dined in a nearby restaurant. A search for Madeleine turned up nothing, and Portuguese police began to suspect her parents. The case made international headlines, and the McCanns denied any involvement.
Gerry McCann said, "We have played no part in the disappearance of our lovely daughter Madeleine."
The couple was eventually cleared and they've carried on a private investigation ever since. That campaign has led to reported sightings of Madeleine from Europe to Africa, yet the trail remains cold.
Kate McCann said, "People are always saying to me 'Are you getting any closer?' and it's a really difficult question to answer because until you know someone says 'Madeleine is here, well, this is the person who's taken her,' you can be really close to her, or you can be a million miles away."
And now the couple's investigation is running out of money.
Gerry McCann said, "It's an expensive investigation and the awareness campaigns that we've done."
Still, the McCanns say they won't stop looking until they know what happened to their little girl.
But apparently, Hill said, the McCanns are keeping Madeleine alive for their other children. In fact, Hill said, the couple's 5-year-old twins talk about their missing sister every day and Madeleine's involved in their role-play.
But what could have happened to Madeleine?
Joseph Moura, an investigative consultant for "48 Hours Mystery," has followed the McCann case for years. He said he thinks Madeleine has been killed.
"I don't believe she is alive and I said it from the very beginning," he told "Early Show" co-anchor Maggie Rodriguez. "This case is the highest publicity case of any kidnapping or missing child that I've ever seen. And anyone who had this child was going to get rid of the child because they just couldn't afford, you couldn't travel throughout Europe and this child would not have been seen. So, I felt from the very beginning, you know, possibly too much publicity on this case was a problem."
But the search continues, despite dwindling funds. Rodriguez pointed out the couple had around $3 million in a fund for their search. What happened to that money?
Moura explained, "Once the initial investigation was handled by the police department, they were fortunate enough to have some celebrities and high-profile people invest money into a fund for the investigation and that's exactly where the money went. They hired three teams of investigators. They chased every lead in the world and, unfortunately, the money is running out. But again, it's a situation where a lot of those leads are just not leading to anything that was concrete. And now they're desperate because they realize that the law enforcement is not going to be able to proceed and they don't have the budget to continue and investigation without any possible leads."
But will the police pick up the case again?
Moura said, "As everybody knows, the McCanns were the number one suspects in this case. They've been taken off the suspect list in Portugal, but unfortunately is that there is an unlimited sources available to continue an investigation without any leads. And the police in Portugal still think that the McCanns were involved in this case and that the investigation is sort of pursued against them. So, they are going to have a difficult team in reference to coming up with additional resources, at least in Portugal, where law enforcement is going to look at this case seriously in any other direction. They are not going to follow the leads all over the world as the McCanns have done with their own private investigator."
The investigation focused on the McCanns in its early stages. Why?
Moura said, "Well, I think originally the situation was -- was, you know, the parents were not as truthful as they should have been in the beginning stages of the case and at that point in time, the police got very suspicious and started pursuing that avenue of investigation and they just, you know, focused on that and unfortunately, at the time, they really didn't go in any other direction. They had a couple other suspects they looked at, but really strongly focused on the McCanns. It's unfortunate but still in Portugal people still believe the McCanns were involved and it's very difficult, at that point, to get the public, at least, behind them in coming up with additional sources and to be able to further the investigation."
The McCanns have also set up a website dedicated to the search for their daughter, FindMadeleine.com.