Nora Quoirin, 15, disappeared almost a week ago from a family holiday.
On Saturday, parents Meabh and Sebastian Quoirin spoke to the media in Malaysia as the search enters a second week.
Holding back tears, Irish-born Meabh said: “We want to say thank you to each and every one of you. We know you’re searching night and day for Nora.
“We see you working so hard and also praying with us and being with us.”
Malaysia is a majority Muslim country, currently marking the Hari Raya Haji, or Islamic “Festival of Sacrifice” celebrations.
“We want to say thank you to each and every one of you. We know you’re searching night and day for Nora”
Meabh Quoirin, mother, Nora
Referring to the event, Meabh went on: “You have given up your time especially at a special festival time.”
She added: “To be with us here, it means the world to us. We are so grateful for everything that you are doing for us, everyone who is helping here and not from here.
“We are extremely impressed by the effort, your expertise, your dedication and we hope you find Nora.”
She finished with the Malay for thank you: “And thank you so much and terima kasih.”
Her French-born husband Sebastian stood beside his wife, rubbing her arm throughout.
Nora – who was born and raised in London – arrived with her parents in the Dusun forest eco-resort in southern Negeri Sembilan state a week ago.
She has an Irish passport and hasn’t been seen since Sunday.
The family fears that Nora – who was born with the brain defect holoprosencephaly – was abducted.
She has severe learning difficulties and needs help with many everyday tasks.
Police have refused to rule out a “criminal element” to the disappearance, but the family say they remain hopeful.
Irish band Westlife – who performed in Malaysia this week – asked their fans to help look for the missing teen, Malaysian media reported.
Before their concert, posters of Nora flashed up on giant screens, while during the gig, band member Nicky Byrne begged the 7,000-strong crowd to help find her.
Anyone with information is asked to contact the Lucie Blackman Trust intelligence on email@example.com or call +44 800 098 8485.