David Wiebe's mother last saw her 13-year-old son ride away on his bike.

It was Steinbach in July1978.

“He was supposed to come to a family barbeque, probably at my place,” said Adele Shidel, his older sister. “He never showed up.”

Their mother called police.

"Everybody was looking for him the whole town I swear was looking for him,” Shidel said.

In December 1994, RCMP arrested Wiebe’s friend Dale Goertzen. The two teens used to shoot targets together.

Goertzen was arrested at Emerson, Man. when he was deported from the United States. He had spent 11 years in a Kansas prison for armed robbery.

He pleaded guilty to second degree murder in Wiebe’s death in April 1995 and has been serving a life sentence ever since.

Thirty eight years later, the Missing and Exploited Persons Unit of the Manitoba RCMP is still investigating.

Wiebe’s remains have never been located and his bike was never recovered.

His parents have passed away. However, his siblings hope RCMP can find his remains so they can lay him to rest with his mother and father.

“We’d like to have a piece of him back,” Shidel said. “I think it would give a little peace back."

RCMP sent out a release about David Wiebe’s story Thursday to mark National Missing Children’s Day.

"It's been 38 years. We haven't forgotten about it and we don't want the public to forget about it, so we've posted his picture online. We want to put the story back out there," said Sgt. Paul Manaigre,

Shidel said RCMP told her they plan to ask Goertzen to show them again where her brother’s remains are. Sgt. Bobby Baker, head of the MEP Unit, told CTV News Goertzen hasn’t been uncooperative in the past, but more information is needed.

“Investigations do not collect dust,” said Sgt. Bobby Baker. “Our investigators look at some of the hardest cases, ones that have not been solved in decades, or cases involving some of the most vulnerable people in society. We do not give up. Even after 38 years, we are optimistic we will be able to locate David and provide some closure to his family.”

RCMP is urging anyone with information to contact them.

"Any leads,” said Sgt. Paul Manaigre, “Our unit will take it and run."