Police have reportedly taken the biggest step in the nine-year investigation of William Tyrrell’s disappearance, recommending charges against the foster mother.

Multiple media outlets report that detectives believe there is enough evidence to charge the foster mother with interfering with a corpse and perverting the course of justice.

The woman, who can’t be named, has been the focus of recent inquiries that the boy fell from a balcony while in her care, and his accidental death was covered up.

The Australian newspaper reports that NSW police have in recent weeks provided a brief of evidence to the Director of Public Prosecutions, recommending the charges.

It is the closest police have come to charging anyone after nine years of inquiry and searching for a body.

However, prosecutors will need to be satisfied there is enough evidence to stack up in court before a decision is made to lay charges.

The news broke late Tuesday, a day after what should have been William’s 12th birthday on Monday.

William was aged three when he went missing from the home of his foster grandmother at Kendall on the NSW mid-north coast in 2014.

A photograph of the grinning child wearing his favourite Spider-Man costume has become one of the most recognisable images of a missing person in Australia.

However, in nearly a decade of investigations, no trace of the boy has been found.

Police have not officially confirmed the latest media reports.

“There are no updates in relation to this matter. The investigation is ongoing,” NSW Police said in a statement late Tuesday.

Initially, William’s disappearance was being treated as a possible abduction. But over time the focus of Strike Force Rosann has shifted to the foster mother, who denies any involvement.

In November last year, Detective Sergeant Andrew Lonergan told a local court he believed Tyrrell’s former foster mother knew where the child’s body was buried.

“I have formed the view [she] knows where William Tyrrell is,” he told Sydney’s Downing Centre Local Court.

In that case, the then 57-year-old foster mother was cleared of lying to the NSW Crime Commission about hitting a different child with a wooden spoon.

In December 2021, a high-profile search around the foster grandmother’s home in Kendall failed to make a breakthrough.

The former foster mother has never been charged for William’s death and there is no suggestion of her guilt.

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One of the initial suspects, washing machine repairman Bill Spedding, was late last year awarded a landmark $1.5 million payout in damages which the state has challenged.

Police searched the tradesman’s Bonny Hills home and drained his septic tank in January 2015, but found no evidence linking him to William, who has not been found.

In December 2021, a highly-publicised month-long search for the possible remains of the missing toddler concluded without any apparent breakthroughs.

Police dug up the garden at his foster grandmother’s former Kendall property, where he disappeared.

They examined a concrete slab laid after that time, drained a nearby creek and sifted through soil in bushland and around the home.

Heavy rainfall at times thwarted the probe, which involved divers, mechanical diggers and dozens of police.

The Sydney Morning Herald reports that the foster mother’s lawyer was on Tuesday night unaware of the latest development in the case.