Cleo went missing on the first night of her family's holiday at the Quobba Blowholes campsite between the hours of 1.30AM and 6AM.
Cleo was sleeping on an air mattress next to her younger sister's cot. Her mother, who was sleeping in the other room of the tent, woke up the next morning to find that Cleo was gone and the tent door had been left open.
Due to the nature of Cleo's disappearance, police suspected an abduction had occurred.
What happened next was a frantic search involving a task force of more than 100 officers. The search for the four-year-old covered air, ground and sea.
Police even scoured through hundreds of bags of rubbish along a 600 kilometre stretch of Western Australia.
A reward of 1 million Australian dollars (€641,750) was offered in exchange for information that would lead authorities to Cleo.
While police have not yet revealed the exact details of what led them to the house in Carnarvon where Cleo was found, Commissioner Dawson told reporters that a "really important" piece of information about a car had pointed them in the correct direction.
He also revealed that several forensic clues were crucial in finding the missing child.
"It's a big jigsaw, you know, everything contributed," he said. "There were lots of things, that when we put the puzzle together it all led to one place, and that's where we found Cleo."
Western Australia Premier Mark McGowan revealed that "various forms" of technology, along with analysis of phone data and social media played a vital role in enabling police to find the correct location.
"As you know, there are thousands and thousands of calls and those sorts of things that can be looked at. They analysed that sort of thing and the social media," he said. "That is a massive task. They did it methodically and in a very painstaking way to uncover information and so I would like to thank them."Explore more on these topics:
