01/16/2017 04:41 EST | Updated 02/08/2017 02:47 EST

Douglas Garland Trial: Court Hears Graphic 'Bloodbath' Details Of Crime Scene (GRAPHIC)

"Something really bad has happened here."

Warning: Graphic details and testimony are included below.

CALGARY — The mother of a five-year-old boy testified Monday that she found blood everywhere — but no bodies — when she arrived at her parents' home to pick up her son after a sleepover.

"I saw pools of blood and hand marks of blood on the wall in front of me, so I thought something was really wrong here. Something has happened here. Something really bad has happened here,'' Jennifer O'Brien testified at the first-degree murder trial of Douglas Garland.

Garland, 56, was charged after the disappearance of Alvin and Kathy Liknes and their grandson Nathan from the couple's Calgary home on June 30, 2014.

O'Brien said she had been helping her mother and stepfather with an estate sale. She was planning to stay the night, but her one-year-old son wouldn't settle down, so she went home for the night. Nathan stayed behind with his grandparents.

Alvin Liknes (left), Nathan O'Brien (centre) and Kathy Liknes (right.) (Photo: Calgary Police Service)

O'Brien told the jury that her mother didn't answer a call early the next morning, but it wasn't until she went over to the house and found the door open that she realized something was wrong.

Inside, there was no sign of her family, just undeniable evidence of a bloodbath.

"Throughout the whole house it was just like a bloody scene,'' O'Brien testified. "There was pools of blood on the side of the bed and on the wall and all throughout the kitchen.''

She went outside and called her husband and told him: "My son ... my family's been murdered and he's taken the bodies.''

O'Brien said she called police who told her to get into her car and lock herself in. She told court that the police officer seized the running shoes she was wearing that day.

"They noticed they were covered in blood and hair which I think was Nathan's.''

"Throughout the whole house it was just like a bloody scene."

Under cross-examination, O'Brien said she had never mentioned before Monday her comments about her family being murdered.

"From what I saw and what my heart told me, I knew my family was murdered. People kept telling me that, 'No, they could be missing,' which raised my hopes, but deep down inside I knew that they were murdered.''

The Crown opened its case by telling the jury that the couple and their grandson were violently snatched in the night and taken to a rural property where they were killed and their bodies burned.

"The three individuals were violently removed from their beds and taken to the Garland farm and killed,'' prosecutor Vicki Faulkner said.

Over a number of days, investigators combed through several properties surrounding the area near Airdrie, north of Calgary, where Garland lived.

Calgary police search an acreage near Airdrie in July 2014. (Photo: The Canadian Press)

The Crown outlined what police found. A burn barrel, still smouldering, contained bones and a small tooth. A tiny piece of burned flesh was found in the grass beside the barrel.

DNA belonging to Alvin Liknes and Nathan was found on a saw. Kathy Liknes's DNA was found on meat hooks.

A bag discovered in one of the outbuildings contained handcuffs, a dagger and a leather baton.

Suspect acted on a petty grudge

Faulkner said Garland was acting on a petty, years-long grudge against Alvin Liknes over a pump patent and had been meticulously planning the killings.

She said Garland did Internet searches to keep tabs on the couple and took action "that took the form of obsessive and methodical planning'' as they were about to move away.

The boy was an unintended victim, Faulkner said, and O'Brien received a terrible shock when she arrived at her parent's home.

Douglas Garland is escorted into a Calgary police station in connection with the disappearance on July 14, 2014. (Photo: Jeff McIntosh/The Canadian Press)

"She did not see her parents. She did not see Nathan. They were gone and all that was left was blood.''

Allen Liknes, the common-law partner of Garland's sister Patti, had known the accused for 16 years and recommended Garland to his father. He said Garland did work with Alvin Liknes on developing a pump but was eventually let go.

"He did get paid,'' said Liknes, who added his wife was the one who told her brother he was fired.

Liknes received a call the day that Alvin, Kathy and Nathan vanished and drove to Calgary to talk to police. He had noticed there was an Amber Alert out for Nathan with a photo of a truck similar to one that Garland would drive.

"I didn't even think of Doug as a suspect at that point and I didn't put two and two together.''

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