They remain hopeful of finding answers in 2015 to the question of what happened to the University of Edinburgh research fellow.
There have been no confirmed sightings of McInnes since he arrived in Geneva on an easyJet flight on September 9th and bought a return ticket to Martigny, 76 kilometers away in the canton of Valais.
The Scottish academic had been due to attend a computer science conference there but failed to show up. He did not check into his hotel, and his suitcase and mobile phone have not been found.
His family have had no contact since with McInnes, who would have turned 52 on October 16th.
McInnes’s father, Bennet, said he thought it “very unlikely” the missing researcher would return home alive, Scottish newspaper The Courier reported online on October 16th.
It said Bennet McInnes believed his son could have fallen while walking in the countryside around Martigny.
Writing on the Missing Fergus blog on January 1st, Fergus’s sister Lorna said she now also believed that “he can no longer be alive”.
“This last Christmas was a strange one for the McInnes family. For my parents, it was the first year Fergus didn’t stay with them over the festive period,” she wrote.
She said that when her father told her, some time ago, that he had come to the conclusion that Fergus must be dead, she couldn’t agree with him.
“Now that we’ve been through Christmas and New Year, I feel the same as my dad … I believe that Fergus can no longer be alive,” Lorna McInnes said.
She said her brother loved “the excitement of giving and receiving presents, eating together, and going for walks on crisp frosty days”.
“It is pretty well inconceivable to me that Fergus would choose not to be at home at Christmas.”
There have been several reported sightings of McInnes since his disappearance but so far no leads.
“What we want, indeed what we feel we need in order to carry on with our lives, is some sort of evidence of what happened to him,” Lorna McInnes wrote in her blog entry.
“We all hope that 2015 will bring answers to this mysterious situation.”