Andrew was aged 14 when he was last seen over a decade ago on Friday, September 14, 2007.
He left his home in Balby, withdrew £200 from his bank account and bought a one-way ticket from Doncaster to London when he should have been on his way to his school, McAuley School in Cantley.
The youngster was last seen on CCTV footage leaving King's Cross station and has not been seen since.
Today well wishers issued statements in support of his family on social media, and issued references to a website which has been set up to trace him, http://helpustofindandrew.weebly.com.
Andrew’s dad. Kevin said he and Andrew’s mum would eat at an Italian restaurant tonight, Andrew’s favourite food, and share stories about him.
He said: “It does seem interminable, not to know where he is for 13 years.
"We still get calls from people though, who say they have seen someone they think looks like him as an adult. Those are passed on to the police.
"It is really encouraging that people are still getting in touch about Andrew after all these years, that there are still people out there who are thinking about Andrew.
"If there is one thing we would like to come of all this, it is that all children have the contact details for Missing People, the charity missing children and adults back together with their families.
"If I could I would tour all year seven school assemblies, asking people to put that phone number into their phones in case they ever need it.”
Earlier this year, a picture of what Andrew might look like as an adult was created and issued to help the search for him.
From old books, favourite t-shirts and even a rocks and minerals collection, Mr Gosden has kept Andrew’s room in familiar fashion as a pleasant reminder of the boy he used to be.
He added: “It just never occurred to us that anyone in our family would ever go missing.”
Visit www.missingpeople.org.uk or call 116 000.