Rui Pedro was 11 years old when he went missing in Portugal in 1988. He has never been found.

The little boy’s disappearance is mentioned in the new Netflix documentary about Madeleine McCann, as a way of explaining why the Portuguese people were feeling unsettled about the attention Madeleine’s case garnered in 2007.

Madeleine’s case is still to this day, the most famous missing child’s case in the world, and has had millions and millions of pounds poured into an investigation trying to find her.

The Disappearance of Madeleine McCann trailer. Post continues after video.

“I can assure you the money police spent on the Portuguese children is not even 1% of what they spent on Maddie,” former detective Paulo Pereira Cristovao told the doco-series.

“Just one girl? There are lots of people, lots of kids kidnapped,” footage of a Portuguese local is also shown in the documentary. His comment reflects the sentiment of many living in the European city at the time.

The documentary poses the question: could Rui and the other missing children in Portugal have had a chance of being found, if they received the same kids of resources as the McCanns?

In Australia 25,000 young people are reported missing every year, in Britain it’s 60,000 and in the EU it’s 250,000, but none of them have received the same kind of level of fame as Maddie.

The William Tyrell case here in Australia as an example is probably one of our highest profile cases, it’s had scores of media coverage over the years since he vanished in 2014. Nothing, however, on the same global scale as Maddie.

It's impossible to choose what stories the public is going to rally behind and put the pressure on. Perhaps it is because so many other families could see themselves in the McCanns shoes, could relate to the horror of a child going missing on holiday.

Or it could just be due to the pressure Gerry and Kate as a couple put on police and the media, they were relentless in their bid to find the three-year-old.

Perhaps with William, it's because of the innocence of playing in his grandmother's back garden that captured Australian's hearts.

It's hard to put a finger on why a story like Rui's didn't garner as much attention as Maddie.

Here's what we know about his story, after being alerted to it in the documentary.

Rui was last seen riding his bike, in Lousada Portugal on March 4, 1998. When he didn't turn up to tutoring later that day, a search began. His abandoned bike was found, but that was the only evidence.

In September of that year, an international child pornography bust saw police recover 750,000 images and videos of 1,263 different children from an illicit paedophile group known as 'The Wonderland Club'.

The only place parents of missing children could see the pictures was in Geneva. So Rui Pedro's mother went over and asked for access.

She found her little boy amongst the faces. He was among the 16 children police were able to identify.

"She was more than a broken woman, she was like a ghost, " Homayra Sellier, president of Innocence for Danger, told the documentary.

Police believe after Rui was abducted and forced into pornography, he was murdered. But they haven't been able to find his body, and prove murder.

Portuguese news outlet TSF reported that on the day Rui went missing, he asked his mother's permission to go for a drive with his friend Alfonso Dias, 22, a local lorry driver.

She had refused, and instead told him to go and play on his bike.

Dias allegedly arranged for Rui to meet a prostitute. The prostitute Alcina Dias, confirmed in court Rui had visited her on the day he disappeared. Dias then left with the boy.

Dias was acquitted in 2012 due to lack of evidence, but was convicted in 2013 in a new trial.

According to the Jornal de Notícias, he was convicted of corruption of a minor, for taking Rui to a prostitute, but wasn't charged with or convicted of anything to do with his disappearance.

Dias was sentenced to three years in prison and maintains his innocence.

When Madeleine's case made headlines in 2007, the Pedro family were furious.

"It is clear they didn't do the same when Rui Pedro disappeared. The extent of the authorities' mobilisation was not as big," his mother Filomena Teixeria told The Telegraph.

In the documentary, Filomena can be seen in footage from 12 years ago saying "they have everything available to them, even a helicopter, things like that. I didn't have that nine years ago. I didn't have anything."

Abduction by sex traffickers, is one of the theories in the Madeleine McCann case, and the one the Netflix documentary focuses most heavily on.

For more on this topic:

Inside the sex trafficking theory linked to Madeleine McCann's disappearance.

Kate and Gerry McCann have two more children Sean and Amelie.

"This could be the breakthrough": Madeleine McCann Netflix documentary claims she's still alive.

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