The first-degree murder trial of a Laval woman accused of killing her two young children began today.

Adele Sorella, 47, pleaded not guilty to two counts of first-degree murder at the Laval courthouse this morning.

In her opening statement, Crown prosecutor Maria Albanese told the jury the bodies of 8-year-old Sabrina and 9-year-old Amanda De Vito were found side by side in the playroom of their Laval home.

She said both girls died at the same time.

Today, crime scene investigators went through dozens of photos, detailing what they found in Sorella's house. For the most part, Sorella was emotionless during the police officer's testimony.

In photos taken at the scene, both girls are shown still wearing their school uniforms.

The jury was told the police seized a hyperbaric chamber, which is typically used to administer high levels of oxygen, from the home.

It was used to treat the younger daughter, Sabrina, who suffered from juvenile arthritis.

Investigators also took jurors through photos of envelopes stuffed with cash in denominations of 100, 50 and 20 that were found stuffed under one of the girls’ mattresses.

Sorella is the ex-wife of Giuseppe De Vito, who was sentenced last June to 15 years for his role in a Mafia attempt to smuggle cocaine into Montreal.

He will be called as a witness at his ex-wife’s trial.

Albanese told the jury that in the months before the deaths of the two girls, Sorella had been depressed and tried to commit suicide several times.

Her mother had come to live with the family in their Laval home.

Sorella, who is out on bail, is being defended by lawyer Pierre Poupart, who also represented Guy Turcotte.

The former St-Jerome cardiologist was found not criminally responsible in the killing of his son and daughter.

The trial is expected to last 6 to 8 weeks as the prosecution plans to call up to 25 witnesses.