Douglas Jesson could tell the little girl in red and white polka-dotted rubber boots had been crying as he watched her being escorted from one car to another by a man who had parked near the girl's home in northwest Calgary.

As Jesson described the tearful child, Taliyah Marsman's family broke down sobbing in the courtroom where Edward Downey is on trial, accused of murdering the five-year-old and her mother, Sara Baillie, 34.

The girl that Jesson spotted on July 11, 2016 was Taliyah, according to the Crown.

Jesson testified he saw the child from a window at the side of his home, which is just around the corner from the basement apartment where Baillie and Taliyah lived in a house in the northwest community of Panorama Hills.

Baillie's body was found in that apartment, stuffed into a laundry hamper that had been pushed into Taliyah's bedroom closet. Two of Downey's fingerprints were found on duct tape wrapped around Baillie's head.

It is the Crown's theory that Taliyah was murdered because she witnessed her mother's slaying, or at least recognized the killer who was inside their home.

Edward Downey, 48, has been in custody since his arrest. His jury trial is set to last until December 14, 2018. (CBC)

Jesson also testified that, on that morning in 2016, he watched as a short, black man walked with a small girl from a white Ford Fusion — which the prosecution says was Baillie's — to a sedan with tinted windows across the street.

The Crown's theory is that the man was Downey, the girl was Taliyah and the sedan with tinted windows belonged to Downey's girlfriend, a woman who can only be identified as "AB" due to a publication ban.

Jesson said the man was wearing a tan jacket and fedora and carrying a suitcase when he placed the child in the back seat of the sedan, got in the front seat and drove away.

Three days after Jesson spotted the girl from his window, Taliyah's body was found east of the city.

Sara Baillie and Taliyah Marsman were killed in July 2016. (Facebook)

On Tuesday, AB testified that by July 11, 2016, her relationship with Downey had deteriorated. She said he had hit her in the face and she had refused to begin working for him as a prostitute.

AB said her best friend, Baillie, "was afraid for me."

In her opening statement to jurors, prosecutor Carla MacPhail ​suggested Downey may have blamed Baillie for AB trying to leave him and refusing to work as an escort.

Under cross-examination by defence lawyer Gavin Wolch, Jesson conceded the girl he saw could have been as old as 10.

Evidence from Downey's cellphone will show it was near Baillie's home on the morning she was killed and then in the rural area where Taliyah's remains were discovered, according to MacPhail.​

Cameras captured cars' movements

On Thursday afternoon, Sgt. Darren Smith testified, showing jurors images captured from cameras on buses, taxis and nearby homes that helped police piece together the movements of the Fusion and Charger.

They show the Fusion was outside Baillie's home until at least 10:13 a.m. and the Charger was on an adjacent street until at least noon.

Images of both cars were captured on the Jessons' street just before 1:30 p.m. and the Charger is seen driving away.

Court of Queen's Bench Justice Beth Hughes is presiding over the trial.