John Murphy, described as a devoted family man, was last seen on 12 May as he left his home in Dennistoun in the east end of Glasgow.
He was last seen at around 7am that morning, when CCTV images showed him emerging from a newsagents carrying a newspaper, apparently on his way to get a bus at nearby Duke Street. However, he has not been seen since and his relatives believe “something went wrong”.
Speaking ahead of the anniversary, Mr Murphy’s son John said although some people believed his father was dead, he and his siblings think he is still in Scotland.
He said: “We believe he is out there somewhere. Personally, I don’t think he is in Glasgow anymore, as I’m certain someone would surely have sighted him by now. But we do believe he is still alive out there somewhere.”
After Mr Murphy failed to arrive at work or return to his home in Craigpark Drive, his family reported him missing. Police Scotland have investigated several potential sightings of the 52-year-old throughout the city and the Greater Glasgow area, including at Cathkin Braes, the Argyll Arcade shopping precinct, Anniesland and Braehead Shopping Centre.
While no sightings have ever been confirmed, John, 25, said he was hopeful the police inquiry would turn up fresh information.
He explained: “The police are going to carry out a few searches in certain areas they couldn’t access previously. But they still have no other leads.”
The family have launched their own appeal for information about Mr Murphy’s whereabouts, setting up a dedicated Facebook page in hope of finding him.
The site has attracted more than 23,000 followers and is regularly updated.
Relatives have also hired a van featuring Mr Murphy’s missing person’s details and raised more than £1,000 to produce and distribute thousands of posters.
Mr Murphy’s son also criticised those who have claimed he had “done a runner” and left his family behind, adding: “Our family is my dad’s life and he would never knowingly hurt us. Something went wrong that morning and he didn’t just get up and leave us.”