Before Madeleine McCann disappeared, eight-year-old Joana went for a walk and never came home.

Three years before the disappearance of Madeleine McCann gained worldwide attention, another little girl from a nearby Portuguese village went missing.

Just like Madeleine, she was never seen again. But the connections between these two cases run deeper than that.

Joana Cipriano’s 2004 murder case is explored in the sixth episode of Netflix’s The Disappearance of Madeleine McCann. In it, we learn that the same detective who led the investigation into Maddie’s case, was also the head investigator for eight-year-old Joana’s.

It contends that Goncalo Amaral botched the 2004 case, and may have done the same to Maddie’s.

However, there's a key difference between the two cases: Joana's disappearance was solved. Her killers were behind bars up until recently - they were released after serving their sentence.

Joana's family reported her missing after she left her home in the town of Figuera, less than 20km away from the Ocean Club in Praia da Luz, where Maddie's parents were dining the night she disappeared. The eight-year-old had gone for a walk and never returned, they said.

Police concluded, however,  that Joana had witnessed her uncle, Joao Cipriano, and mum, Leonor Cipriano, having sex. For that, the pair killed her and disposed of her body, they said. Although Joana's body was never found, police said they found drops of her blood in different parts of the family home.

But what really closed the case was Leonor's confession. It allowed police to proceed with a trial that found the mother guilty and sentenced her to 16 years jail. Joao, meanwhile, was given a similar sentence.

Around the time of Madeleine's disappearance though, questions were being asked about how this confession was obtained after the mum retracted it. She said she only confessed after being beaten, and had the photos of her swollen face to prove it. Police claimed the bruises were a result of her throwing herself down the stairs.

The men accused of beating and torturing Leonor were acquitted, but in 2009 the truth was settled when Goncalo Amaral was handed an 18-month suspended jail sentence for covering up the abuse, the Telegraph reported at the time.

So in the eyes of the law, the beating had happened, but it wasn't until March 2019 that Leonor and Joao were released, after serving almost the entirety of their jail sentences, according to local reports.

According to the Netflix documentary, Joana's case is evidence of Amaral's unhelpful fixation on the involvement of parents in their child's murder.

"When they see that they don’t have any lines of investigation or clues, they blame the parents directly," the Spanish private detective who was hired by the McCann family to investigate their daughter’s disappearance said.

“It’s not a case about finding Joana. It’s not a case about finding Madeleine McCann. It’s a case about finding evidence against the parents."

Amaral was removed from Madeleine's case five months into the investigation in 2007. His working theory had been that Maddie's parents, Kate and Gerry McCann, had accidentally or intentionally killed their three-year-old daughter and hid her body to cover it up.

Both Kate and Gerry maintain they had nothing to do with their daughter's disappearance.

As for Joana, if her mother and uncle didn't kill her, then where is she?

Well, the Netflix docu-series offers up a theory: the pair sold Joana to a foreign family and she is still alive.

Joao's former cellmate said that the uncle even showed him photos of a kidnapped Joana in a room that was "not from somewhere poor".

When asked if he thought the girl, who would now be in her early 20s, was still alive, he said: "For me, from what I’ve seen, I have no doubt".