"We're very hopeful that they're out there. There's no doubt in our mind," said the boy's mother, Jennifer O'Brien, choking back tears as her husband, Rod, stood with his arm around her shoulders.
"We've just got to find them and the police are doing everything they can do. I'm hopeful in every way and we all are. I hope this turns out to be a happy story and I think it's going to."
Nathan O'Brien and his grandparents, Kathryn and Alvin Liknes, haven't been seen since June 29 after what police say was a violent incident in the Liknes home. The couple had been having an estate sale and were downsizing ahead of a move to a home in Edmonton and then on to Mexico. Nathan was at their house for a sleepover.
About 500 people turned out for a candlelight vigil at the Parkhill Community Centre, just around the corner from the Liknes home.
Green ribbons, recognized as a symbol to remember missing children, were handed out to those attending. A moment of silence was held followed by a lighting of the candles. Throughout the ceremony, tears streamed down faces and some people were sobbing.
About a dozen friends and family members slowly made their way up to the microphone, sharing anecdotes and hoping for the best.
"I like to think of this whole thing as just a way to keep the flame going," said Jeff Liknes, Kathryn and Alvin's son.
"I don't want to think of this like a funeral because I know it's not one. I'd love to see them again."
Randy Prevost, Kathryn Liknes's brother, told reporters he wanted to help in the search but police asked the family to not get involved in the investigation. He remains hopeful but said it has been a tough two weeks.
"Never in my wildest dreams could I imagine anything like this," he said. "You've watched movies and seen things like this, but it's not real."
He repeated the family's mantra of holding onto hope.
"I just want to look into each one of their eyes and cry for a while because it's going to be a gracious moment when it does come around."
Police say they are looking into the family's business dealings as they continue their search.
There are reports that the grandfather, Alvin Liknes, was recently forced to close his small gas exploration company.
There are also reports that he once had a bad business deal with Douglas Garland, whom police say they have questioned as a person of interest in the case.
"We are aware of some business issues regarding the family and so we have officers and investigators that are looking at that to see if there's a connection to this disappearance," Calgary Police spokesman Kevin Brookwell said Thursday.
"I can't get into specifics as to what those are, who was involved, what they look at or how many people are involved, but yes, we have investigators looking into those allegations."
Officers continued to search property owned by Garland's parents north of Calgary. Garland was taken in for questioning last weekend and has since been held on unrelated identity theft charges.
Police are also scouring city garbage dumps for evidence, but say that's standard procedure.
"Shortly after the disappearance was reported we made contact with the three landfill sites in Calgary and we asked that all refuse from the Calgary and surrounding area that goes to those landfill sites be segregated off," Brookwell said.
"There have been items that have been taken from the landfill site, but we don't know if there's any relevance to this file or not. You can appreciate that we're talking about all landfill that was collected for a number of days following the disappearance, so there is quite a quantity to go through."
Some online business directories link Alvin Liknes with several oil and gas companies, including Vecto Resource Services, Bluesky Oil and Gas Corp., and AKF Holdings Inc.
Metro Calgary has reported that his latest business venture, a small firm called Winter Petroleum Ltd., was forced to close a few weeks ago after it had its equipment seized over $800,000 in owed taxes. The National Post reported Alvin Liknes declared bankruptcy in 1994. His wife, a real-estate-agent-turned-website-design consultant, did the same in 2012.
Other media have quoted an unnamed police source saying Alvin Liknes had a bad business deal several years ago with Garland, but no details have emerged about it.
Court records show Garland has a criminal past and mental health problems. In 2000, he was sentenced to 39 months in prison for making amphetamines at his parents' farm.
Police have confirmed his sister is in a relationship with a member of the Liknes family.
Garland could be released as early as Friday, when he is next scheduled to be in court.
"If he is released, he still remains a person of interest in this investigation, but he still hasn't been formally charged," said Brookwell.
The search for the missing family entered its 11th day Thursday, but Brookwell said police are also not giving up hope the three will be found alive.
"Until we get the information or evidence to change that, and at this point we have not," he said. "We are hopeful and will remain that way until something changes."
— With files from Chris Purdy in Edmonton.
— Follow @BillGraveland on Twitter
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