A detective who worked on the Madeleine McCann case says it has similarities with the recent disappearance of a UK teen holidaying in Malaysia.
Nora Quoirin, 15, disappeared from her room in a resort south of Kuala Lumpur on Sunday. She has special needs.
She was on holiday with her parents - an Irish-French couple - and younger siblings, the BBC reports.
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When they woke up the morning after they arrived, her father went to her bedroom but Nora was nowhere to be seen.
Child protection expert Jim Gamble said it was a rare situation.
"Ultimately, the cases of children going missing abroad are so rare that we tend to know the names of all of them," Gamble, who investigated Madeleine's disappearance, told The Sun.
"This is now one of three cases that are similar... Ben Needham who went missing many years ago, Madeleine McCann who is still on everybody's minds and now Nora."
Malaysian police are scouring the area near where Nora disappeared, using recordings of her mother to aid the search.
Nora's London-based family believe she was abducted and police admitted that was a possibility on Thursday after finding unidentified fingerprints.
Police also released a photo of a downstairs window of the cottage where Nora was staying, which was accidentally left open the day she went missing.
The family released an emotional statement on Wednesday saying they believe it's possible Nora will be found.
"This is extremely traumatic for the whole family. [Nora's parents] Meabh and Sebastien are devastated and too upset to speak themselves at this time," Nora's aunt said, speaking on behalf of the girl's parents.
"But we must remain hopeful and we ask everyone to keep Nora in their thoughts, and to continue to support the ongoing search for her.
"Nora is still missing, and she is very vulnerable, and we need to do everything we can to bring her home."