Zane Gbangbola died after the River Thames flooded his Surrey home in 2014.
His parents disputed the results of an inquest in 2016 and say their son was killed by gas washed out of a former landfill site in Chertsey.
Kye Gbangbola said the system which failed Post Office workers had failed his son "in a very spectacular manner".
"We know the system doesn't work and in this case, for Zane, it truly didn't work," Zane's father added.
Mr Gbangbola and Nicole Lawler, Zane's mother, have joined MPs in calling for an independent panel inquiry.
They say the report from Surrey coroner Richard Travers was flawed, claiming the full evidence wasn't made available to the inquest.
Mr Travers concluded Zane died from carbon monoxide from a petrol pump used by his parents to remove water from their flooded home.
But the couple say the petrol pump was not used and have obtained public health documents that say no carbon monoxide was found.
A spokesman for the coroner's office said that "an independent, full, frank and fearless inquest" concluded in 2016.
The couple, who had to leave their flooded house a decade after their son died, said a historic landfill nearby was still unsafe.
Ms Lawler said: "Nothing has been done to remediate that land or to stop it from flooding. No lessons have yet been learnt. Government bodies such as the council and the Environment Agency used the flawed coroner's report as an excuse to do nothing and to look away."
Last Thursday, MPs tabled an Early Day Motion (EDM) calling for an independent panel inquiry and said in Zane's case the victims and bereaved had been "blamed, abused and scapegoated".
The motion said there had been a lack of proper investigation, masses of evidence undisclosed or ignored, and a "flawed judicial outcome".
The EDM, tabled by Hillsborough survivor and Liverpool West Derby Labour MP Ian Byrne, said the Post Office scandal had reemphasised the need for a Hillsborough Law and more cases would benefit from the transparency measures called for by Hillsborough Law campaigners, including Zane's parents.
In the Post Office scandal, hundreds of sub-postmasters and postmistresses were wrongly prosecuted after faulty computer software calculated money was missing from Post Office branches.
And last year, the government responded to a 2017 report calling for key reforms following the 1989 Hillsborough disaster, but families said pledges did not go far enough.
During the 10-year campaign by the family of Zane, they obtained Public Health England papers which said the fire service detected no carbon monoxide.
Mr Gbangbola said: "People are now very familiar with things like the sub-postmasters and sub-postmistresses and the way in which they were treated and [how] they went through proceedings through the courts but the outcomes were incorrect.
"Hillsborough went through processes, proceedings, inquests - the outcome was incorrect.
"It is now 10 years to the day when Zane was killed in a house infused with hydrogen cyanide."
A pledge to consider a public inquiry for Zane was included in Labour's 2019 manifesto and the couple have called on their Conservative MP and ex-chancellor Kwasi Kwarteng to help them before he stands down at the next election, by ensuring Zane has an independent panel inquiry.
Zane's parents will attend a memorial service on Thursday to mark the anniversary of his death, and have asked people to remember their son for the person he was as they continue to fight for truth.
Mr Gbangbola said: "We are a family where every day we have to talk about how our child died.
"This should be an opportunity to be able to speak about how [he] lived."
He said: "We feel the pain of Zane's death every day."
Describing him as a "remarkable little boy", Mr Gbangbola said: "He was bright, clever, and he did many things in the time that he was with us.
"He was a little environmental activist. He helped found his school's environmental team across the middle, lower and upper schools.
"He read at the age of a teenager, when he was only six years old. He raised a lot of money for different charities. Zane loved people and people loved Zane.
"He had every reason to live a full life but he was let down.
"So we cherish our memories of Zane as a beautiful child and we fight for truth."
A government spokesperson said: "This is a tragic case and our thoughts remain with the Gbangbola family. Throughout the inquest, the Environment Agency provided detailed evidence to assist the independent coroner in reaching his conclusions."
Spelthorne council declined to comment.
Original article by By Tanya Gupta & Adrian Harms BBC News, Chertsey