Police had first received a missing person report on Saturday morning, and confirmed that the North Shore teen had not been seen since the evening before.

On Sunday evening Stewart made a desperate plea on social media appealing for any sightings of the missing teen who she had not seen all weekend.

The mother said her family was "absolutely sick with worry" over Mia's disappearance.

"This is by far the hardest thing I have had to write and we do not want or need anyone's judgement, gossip or speculation.

"We just need your help.

"Mia aged 15 has been missing since Friday 14h of December from North Shore/Hibiscus Coast and her phone hasn't been used and she hasn't been online since just after midnight on the same night after being with some people that she doesn't know very well."

The post went viral on Facebook with more than 44,000 people sharing her message and an outpouring of supportive messages rushing in for the family.