The balloons were released in many communities across Alberta, a show of support for the families of the boy and his grandparents Alvin and Kathy Liknes, who police now believe were slain after they vanished June 29.
No bodies have been found.
Tears rolled down Rod O'Brien's face as he tried to comfort his son Luke, who had his arms wrapped around his neck. He had one arm around his wife, Jennifer, as they huddled together to watch the balloons fly away.
Each one of the balloons contained a message written in felt pen.
"We love you, Nathan," read one.
The tribute came hours after Calgary police officially laid charges against Douglas Garland, 54, who had been under investigation in the trio's disappearance. Garland has been charged with first-degree murder in the deaths of the older couple and second-degree murder in the death of the little boy.
Several family members took in the ceremony in the playground directly across the street from the O'Brien home.
"They're absolutely crushed," said Jeff Liknes, who has been staying with his sister, Jennifer.
"I never would have been able to go through this without my family. It's nice that people are looking out for us. People that I've never met before have come out to show their support. It's amazing, actually."
Like other family members, he has not given up hope that his parents and nephew may still come home safely.
"I know the cops don't really think so but I know my mom is really strong," he said. "My parents were really strong. There's just so much energy and so much life in them. If anybody's going to make it through this it's going to be them."
Negin Elsami runs a local dayhome and had taken care of both Nathan and his two younger brothers.
"He was such a sweet little boy," Elsami said, wiping away a tear. "I've known him since he was 11 months and he was very kind, very helpful, always hugging everyone. He was so excited about finishing his kindergarten and going into Grade 1.
"It's heartbreaking. I can't believe it and I'm just praying and hoping that he's alive and he's coming back to us."
Shortly after the trio disappeared, Nathan's parents issued a tearful plea through the media asking for their return and urging their "superhero'' son to be brave.
A memorial that started Monday on the front lawn of the grandparents' home has grown to include flowers, balloons, teddy bears and a children's Superman shirt.
An acreage near Airdrie, Alta., where Garland lived has been the focus of a massive search by police and on Tuesday, two mothers in the community organized a civilian search party to begin looking for clues or evidence that could lead police to the bodies.
One of the organizers, Tara Murphy, said they won’t go on to private property without permission and will speak with rural landowners to echo Hanson’s message to search land for anything suspicious.
Murphy said police haven’t approved the search but also haven’t told the group not to do it.
Despite the charges, police Chief Rick Hanson has said the case is not closed and investigators will continue to search for the bodies.
Hanson renewed calls for rural property owners to search their land for anything out of the ordinary.
Garland has ties to the Liknes family. His sister is in a relationship with a member of the Liknes family.
Police earlier said they were looking into whether there was a business connection to the missing persons file.
Alvin Liknes was involved in several oil and gas companies, including Winter Petroleum Ltd., which media reports say was forced to close a few weeks ago. The CBC has quoted a police source as saying Garland and Alvin Liknes had a dispute over a patent for a gas device.
Court documents show Garland has a criminal record and mental issues.
In 2000, he was sentenced to 39 months for making amphetamines at his parents' farm. Before he went to prison, he jumped bail and lived for several years in Vancouver using the identity of a dead person.
The Parole Board of Canada gave him accelerated release after six months, noting in its decision that Garland's prior criminal record consisted of various property offences over the course of 20 years.
His mental health played a role in the crimes, the board said, but a psychologist determined that Garland had "little violence potential to others.'' It ordered a psychologist and psychiatrist to closely monitor him during his release.
Garland's next court appearance is scheduled for Wednesday.
— With files from CFFR
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