There are mounting concerns for little Cleo Smith's safety as the search for the missing four-year-old at a remote campground enters its fourth day, with close friends of the family warning 'she would not have wandered' off.
The four-year-old was last seen by her mother Ellie Smith in bright pink pyjamas about 1.30am on Saturday inside the family's shared tent at Blowholes campsite, north of Carnarvon, in Western Australia.
Ms Smith and her partner Jake Gliddon had an 'interaction' with the youngster in the middle of the night, but she was nowhere to be seen when they woke up at 6.30am and her grey and red sleeping bag was also missing.
Her biological father Daniel Staines spent nearly three hours in Mandurah Police Station on Monday, 1,000km south from where Cleo disappeared, after voluntarily coming in to give a statement.
Investigators have not ruled out anything in relation to her disappearance and are exploring theories she may have been abducted - with homicide detectives working 'a million miles an hour' to find her.
Police refused to confirm reports a car was heard skidding off as it left the area around 3am on Saturday, after other campers reported the odd noise.
Meanwhile, social media sleuths who are trying to crack the case from home have shared several other concerning possibilities.
There are mounting concerns for little Cleo Smith's (pictured with her mum Ellie and partner Jake Gliddon) safety after she went missing at a remote campsite on Saturday morning
The four-year-old (pictured) was last seen by her mother Ellie Smith in bright pink pyjamas about 1.30am on Saturday inside the family's shared tent at Blowholes campsite, north of Carnarvon, in Western Australia
The camp ground is located 75km from Carnarvon and 875km from Perth with nothing but bushland and scrubs in between
1. Swept out with the tide
One possibility is that little Cleo may have woken in the night and wandered toward the nearby ocean, only to have fallen off a dangerous cliff and been swept away by rising waters.
The tide was at its lowest at 12.51am and gradually rose until 6.16am, when it reached high tide.
First light occurred at 5.25am, while sunrise was recorded at 5.48am.
While the area is known for strong tides, exhaustive marines searches over the past three days have so far found no evidence Cleo and her sleeping bag entered the water.
'The searches we have done for this marine environment are the best we can get and they have done the best they can, and in that environment we haven't found any sign of Cleo,' Inspector John Munday, who is leading the police search, said on Monday.
'And that marine search has been scaled back at this time.'
One possibility is that little Cleo (pictured) may have woken in the night and wandered toward the nearby ocean, only to be swept away by rising waters. But so far marine rescuers have found no evidence of this
The Blowholes campsite is also known as Point Quobba (pictured) and is a popular but remote camping destination
The desperate search is entering its fourth day with police releasing footage of the remote campsite (pictured) where she disappeared
A chart shows waters were at low tide on the night Cleo went missing without a trace from her mum's tent
2. Fell down a hole-in-the-ground toilet
The grounds of the campsite and surrounds are flat and bare, making it easy for helicopters to scan the area from the skies above.
But locals and passersby who have visited Blowholes before say the site is littered with sheds and drop holes usually used as toilets.
There are fears Cleo may have wandered off in the dead of night, only to fall into one of the many holes nearby.
'Are the toilets out there "long drops" still or done up? How far away are the toilets from their camp?' one person asked on the Bring Cleo Smith Home Facebook page.
'Just asking did anyone check?'
SES crews, volunteers, Indigenous bush trackers and homicide police confirmed they have been on the scene tirelessly searching the surrounds for three days but found nothing.
Those close to the family have also dismissed the idea.
'She is an intellectually advanced little girl,' a family friend told the West Australian.
'She is a smart little girl and she would not have wandered.'
There are fears Cleo (pictured) may have wandered off in the dead of night, only to fall into one of the many holes nearby. But close family friends insisted the four-year-old wouldn't do that
SES crews, volunteers, Indigenous bush trackers and homicide police confirmed they have been on the scene tirelessly searching the surrounds for three days but found nothing
The most widely accepted theory circulating online is that little Cleo was abducted.
Police say they have grave concerns for the child and that 'everything is on the table' in the unusual and disturbing case.
Late into the third day of the search investigators made a public plea for anyone who was anywhere near the campsite from Friday to Sunday, to come forward and contact police - particularly if they have dashcam footage.
They said it will assist police to track and trace the movement of everyone in the area, raising speculation a kidnapping is now the main working theory of what happened Cleo.
The camp ground is located 75km from Carnarvon and 875km from Perth with nothing but bushland and scrubs in between.
Internet sleuths suggest police search dogs would have found the girl by now if she was still in the area because the campsite is bordered by the ocean on one side and desolate, flat, rugged terrain on the other.
Another element which has raised suspicions she was snatched is that her sleeping bag is also missing.
Some campers reportedly heard a vehicle speed off at about 3am on Saturday, but police have so far declined to comment on the matter.
It has been confirmed that detectives have seized CCTV footages from roadhouses in the area as part of their investigation.
The most widely accepted theory circulating online is that little Cleo (pictured) was abducted
Police have released an image of Cleo's sleeping bag and are urging members of the public to come forward if they have seen it
4. Mediums claim 'green rusty tin door' is involved
Several people claiming to be mediums, and who are not directly linked to the family, have also expressed concerns about a potential abduction.
One woman insists a 'green rusty tin door' is crucial to finding the four-year-old after seeing it in a vision.
'May I please have a map ASAP,' the woman who claims to be a professional medium said on social media.
'Green rusty garage tin door needs looking into.'
While there is no evidence her premonition holds any significance to Cleo's disappearance, another Facebook user pointed out a curious fact about the camp grounds.
One woman insists a 'green rusty tin door' is crucial to finding the four-year-old after seeing it in a vision - while another pointed out there are similar doors at the campsite
'There are camp sheds with spray painted numbers throughout the whole camp site,' the person wrote.
'They are green, tin and rusty.'
A second so-called medium indicated she sees 'a hole... also possibly a blue 4WD' and 'her crying for her mum'.
But with the family and the Facebook page bombarded by those claiming to have supernatural abilities, moderators have begun deleting 'medium posts'.
Anyone who may have any information about Cleo's disappearance is urged to contact police immediately.
Police say they have grave concerns for the child (pictured) and that 'everything is on the table' in the unusual and disturbing case
A second so-called medium indicated she sees 'a hole... also possibly a blue 4WD' and 'her crying for her mum'
With the family and the Facebook page bombarded by those claiming to have supernatural abilities, moderators have begun deleting 'medium posts'
While investigators still have no solid leads about the mysterious disappearance, there was a development on Monday afternoon.
Cleo's biological father, Mr Staines, spent three hours inside a police station on Monday after detectives asked him to make a statement.
Seven News reported he was at work during the morning before coming into Mandurah Police Station, 1,000km south of where Cleo vanished, of his own accord with his parents by his side.
There is no suggestion he has anything to do with his daughter's disappearance.
Friends of Cleo's family said the smart four-year-old (pictured) 'wouldn't just wander' away from the tent
Daniel Staines (pictured, right) went to Mandurah Police Station - 1,000km from where she disappeared - to give a statement about his daughter's disappearance
Police roped off the area where Cleo vanished from her tent in the middle of the night (pictured) as they continue to investigate her disappearence
Inspector Jon Munday said there are 'grave concerns' for Cleo as the hunt to find the little girl gets more desperate 'every hour'.
'With a four-year-old out in this environment… there is limited water supply, it is warm, there is very limited shelter so it is very, very concerning,' he said.
Cleo has reportedly visited the area with her mother on camping trips since she was a baby.
Investigators are concerned rain expected on Tuesday may hamper the search, but said they would keep up efforts for another 48 hours, at least.
Her devastated mum and her partner have stayed at the campsite to assist the search, desperately hoping the four-year-old will emerge.
Police are calling on anyone who was anywhere near the area over the weekend to come forward, particularly if they have dashcam footage as it may help to 'track and trace' the movements of people in the vicinity.
'We are really interested in anybody who was at The Blowholes campsite from Friday the 15th of October through to Sunday,' Inspector Munday said.
Cleo Smith, four, (pictured) was last seen at about 1.30am on Saturday at the Blowholes campsite on the coast at Macleod, north of Carnarvon, in Western Australia
'You don't even have to have stayed here, even if you just passed through. We need to speak to you... so we can track and trace where people were.
'And if anybody has any dashcam footage or any footage at all of the area we really would be interested in those people coming forward.'
The child's mother in a Facebook post on Saturday morning made her own public plea.
'It's been over 24 hours since I last seen the sparkle in my little girl's eyes! Please help me find her,' Ellie Smith wrote.
'Last seen 1.30am and gone when woken up at 6am from our shared tent. Very very unusual for Cleo. Please if you see anything unusual or suspicious call the police.'