The parents of ​Etan Patz​, the little boy who went missing on his way to school in 1979,​ are asking a Manhattan civil judge to reverse a 2004 ruling that said convicted child molester Jose Ramos killed their son.

The request comes just weeks before ​former bodega worker ​Pedro Hernandez is set to be retried for the 6-year-old’s disappearance and death.

Hernandez’s first murder trial resulted in a hung jury last year. In closing statements​,​ Hernandez’s attorney, Harvey Fishbein, argued that Ramos was Patz’s real killer.

To remove any doubt about who the parents think murdered their son for the second go-round​, ​dad Stanley Patz filed a sworn statement in Manhattan civil court Wednesday.

“Despite the lack of resolution in the first trial, after reviewing all the facts relating to the crime against Etan, and after sitting through the trial and hearing all the evidence, my wife and I — the parents of Etan Patz — now believe that Pedro Hernandez and not Jose Ramos was the perpetrator of this heartless crime,” the affidavit says.

Ramos once told a federal prosecutor that he had tried to have sex with Etan.

Stanley Patz ​and his wife​,​ Julia​, filed the wrongful death case against Ramos in 2001, decades after their son went missing in 1979.

Ramos, who is in jail for other crimes, was found guilty in 2004 and hit with a $2.7 million judgment. He has not paid any amount of the award.

The Patz filing angered Herndandez’s attorney.

Fishbein wrote a letter to the judge overseeing the upcoming criminal trial. He quotes a statement by the Patz’s attorney, Brian O’Dwyer, saying “Stan doesn’t want anybody to think that he doesn’t think Hernandez is the cultprit.”

That statement is “a blatant assault on Mr. Hernandez’s ability to receive a fair and impartial trial,” Fishbein says. He’s asking the judge for a hearing on the matter before jury selection starts on March 7.