EDMONTON -- When Trudy Holder arrived at the airport in Abbotsford, B.C., she looked around for her parents, but they weren't there to pick her up as planned.

Holder told an Edmonton murder trial Thursday that Lyle and Marie McCann, 78 and 77 respectively, always kept their commitments.

"My mom and dad are never not there," Holder testified. "I started freaking out."

Holder and her daughter had flown to Abbotsford from their home in Calgary to meet the McCanns.

It was July 10, 2010. Holder began making frantic phone calls and discovered her parents had not checked in to a nearby campground where the family was to spend the next two weeks on holiday. She also phoned her two brothers, a friend of her parents and the RCMP to report the seniors missing.

Travis Vader, 44, has pleaded not guilty to first-degree murder in the deaths of the couple.

Although their bodies have never been found, the Crown is arguing the two were killed by Vader, described as a crystal meth user who had been living in makeshift camps in an area west of Edmonton.

Court heard the McCanns were last seen fuelling up their motorhome and buying groceries at a Superstore in their hometown of St. Albert, a bedroom community north of Edmonton, on July 3, 2010. They were setting out to meet Holder in Abbotsford.

But they didn't make it far.

Two days later, their RV was found burning in the bush about 200 kilometres west of St. Albert. The Hyundai Tucson they had been towing was found hidden in some trees on a nearby rural property about a week later.

Photos entered as evidence show there was nothing left of the motorhome but a burned shelled.

Forensic anthropologist Owen Beattie testified that he sifted through the debris after it was put in a large garbage bin at RCMP headquarters in Edmonton.

He found no trace of the McCanns.

"We determined there was not a presence of human remains," he said.

Beattie added that it was unlikely animals scavenged any remains, because they would have left some behind. He also testified that it would be unusual for a fire to reduce a body to dust, although not impossible.

The McCanns were avid campers who packed their motorhome full of potatoes, beans and fishing gear -- along with a cellphone for emergencies -- before setting out each summer, said their daughter.

She described her father, a retired long-haul trucker, as a cautious driver who took impeccable care of his RV.

"My mom was my best friend," Holder, 54, said through tears. "I would talk to my mom every day.

"We talked about everything that was going on."

Holder said both her parents were healthy, but her father had started acting unusual in the weeks before the couple vanished. It troubled her that he had been curt with her during two phone conversations and she was going to ask him about it on their B.C. holiday.

Holder said she last spoke with her father on the morning of July 3 when then McCanns hit the road.

He told her, "We're on our way," she said.

"We'll see you in a week or so."'