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Police are making headway in the case of the two missing Nova Scotia children, said RCMP Staff Sergeant Rob McCamon, acting officer in charge of Major Crime and Behavioural Science.Ingrid Bulmer/The Globe and Mail

The question of how two young children could just disappear has kept the RCMP head of major crime in Nova Scotia awake for many nights since Jack and Lilly Sullivan were reported missing from their home last May.

But Staff Sergeant Rob McCamon, the acting officer in charge of Major Crime and Behavioural Science, insists police are still making progress with the case and he’s confident that in time it will be resolved.

“This is not a file that just sits at work, and you pick it up in the morning,” said Staff Sgt. McCamon. “… You’ve got two very vulnerable people who perhaps were in some difficult circumstances and they’ve gone missing. We need answers as to what took place.”

A team of major crime investigators are still following up on the more than 1,000 tips they received, and working through a list of 1,300 investigative tasks in a case that Staff Sgt. McCamon described as having the greatest volume of information in his 25-year career.

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Lilly and Jack Sullivan, shown in a photo held by their paternal grandmother Belynda Gray, were reported missing on May 2.Darren Calabrese/The Globe and Mail

The disappearance of Jack, 4, and Lilly, 6, from their home in the rural hamlet of Lansdowne has reverberated across the country and abroad – a missing persons case that Staff Sgt. McCamon described as affecting so many because it’s “a very fundamental wrong.”

On May 2, the morning Jack and Lilly were reported missing, their mother, Malehya Brooks-Murray, marked them absent from school for a second day in a row. Around 10 a.m., she called 911 to report they had wandered off while she and their stepfather Daniel Martell had been dozing in bed with their toddler.

Staff Sgt. McCamon declined to speak about an investigative theory or theories in an interview at Nova Scotia RCMP headquarters in Dartmouth this month, saying all avenues are still under consideration and he has to consider the impact on “long-term justice” should criminal charges be laid. But he added police are making headway.

“I believe we have made ground when it comes to where things are heading and what we’re finding out,” he said.

“We’re collecting information from all areas. We’re assessing that and it’s helping us form pictures of what may have taken place. We’re going to continue to work down that road.”

Court documents reveal items seized and found by police during search for Jack and Lilly Sullivan

The Globe previously reported on troubling issues inside Jack and Lilly’s home – including admitted drug abuse by their stepfather, multiple black eyes on the children, controlling behaviour that affected their mother and other pressures brought on by the parents’ financial struggles.

The Globe’s reporting also revealed that a provincial child protection social worker had visited the children’s home to investigate a report of suspected abuse or neglect.

Staff Sgt. McCamon said police interviewed the social worker involved with Jack and Lilly, and others with valuable information about the children’s circumstances.

“We have looked at their movements in the days prior and the kind of things that were going on in their lives – that is part of our investigative inquiry,” he said.

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Staff Sgt. McCamon said the investigative team is following up on more than 1,000 tips.Ingrid Bulmer/The Globe and Mail

Both parents explained the children’s sudden disappearance the same way: The kids must have put on their boots, opened the sliding glass door, and left the fenced-in backyard. The three adults who live on the property, including the children’s step-grandmother Janie MacKenzie, told police they heard the children playing in the morning before they disappeared.

In the days and weeks that followed, the Mounties oversaw one of the largest searches in the province’s history. Dozens of search and rescue teams, police dogs, a helicopter and drones scoured the thickly wooded area around the trailer for more than 12,000 hours. They reviewed thousands of surveillance videos and human remains detection dogs pored over 40 kilometres of land.

In late fall, the children’s stepfather, Mr. Martell, said he doesn’t believe the children wandered into the woods anymore because of the extensive search. He said he also no longer suspects that Ms. Brooks-Murray, who ended their relationship shortly after Jack and Lilly disappeared, was involved in the abduction of her own children – a theory he had suggested.

Both parents have repeatedly denied any involvement in Jack and Lilly’s disappearance, and court documents show they both underwent polygraph tests that found they were truthful on all four questions that were not publicly disclosed.

No new searches for the children are planned, but Staff Sgt. McCamon said police are reviewing the search areas to ensure they haven’t missed anything. “If we identify areas that we feel would be of benefit to do some more searching, we will,” he said.

Grandmother of Jack and Lilly Sullivan calls for public inquiry into children’s disappearance

Without answers, social media and online content creators have more than filled the void, sometimes mashing facts with misinformation and speculation.

While these online communities help keep the case in the public eye, Staff Sgt. McCamon said they can also hamper the investigation. It takes investigators time and resources to look into tips garnered from what in some cases has turned out to be “just a comment made on social media,” he said.

Staff Sgt. McCamon said he understands the urgent need for answers about what happened to Jack and Lilly but cautioned that intensive major crime investigations take time to do things by the book and according to the Canadian Charter of Rights and Freedoms.

“We have to consider whether charges will be laid eventually. So we have to maintain the rule of law and follow the rules that are there. It does take time and it is going to take some more time,” he said.

“We won’t stop until we have answers as to what happened with Jack and Lilly.”