LAVAL -- After three days of deliberations, a jury in Laval has found Adele Sorella guilty of first-degree murder in the deaths of her two young daughters.

The jury found 47-year-old Sorella guilty just before 11:30 Monday morning of killing her two daughters Sabrina, 8, and Amanda, 9, inside her family home on March 31, 2009.

She had been free on bail since 2010.

Sorella appeared calm, showing little emotion. After the verdict was read, she  hugged her lawyer before she was escorted out of the courtroom.

The first-degree murder verdict comes with an automatic life sentence with no chance of parole for 25 years.

Defence lawyer Pierre Poupart had no comment after the verdict.

Crown prosecutor Maria Albanese said, "We're happy with the verdict, obviously. We consider that it wasn't an easy file. It was difficult for a lot of people. Everyone worked really hard. The members of the jury also worked very hard to render their verdict today."

The jury had been locked in deliberations since Friday, and had to choose from four options in the verdict: first-degree murder, second-degree murder, manslaughter or acquittal.

Throughout the eight-week trial, Sorella chose not to take the stand in her own defence.

Although she was diagnosed as suicidal and had spent time the Pinel Institute for mental health, her legal team did not try to invoke insanity as a defence.

 The jury of seven women and five men heard from 51 witnesses, including Sorella's estranged husband, convicted mobster Giuseppe De Vito, who was on the lam when the girls were killed. He is currently serving a 15-year sentence for gangsterism and drug trafficking.

It also heard from pathologist Caroline Tanguay earlier this month, who told the Laval jury that she couldn’t conclude exactly how Sorella’s two daughters died said evidence showed asphyxiation; the girls were likely smothered with a pillow, killed by having plastic bags placed over their heads or killed by being deprived of oxygen in an enclosed space.

The prosecution argued the children died of asphyxiation through a hyperbaric chamber Sorella purchased to treat her daughter’s juvenile arthritis. If the oxygen in it is turned off, the sisters would have slowly fallen asleep and died 90 minutes later.

The defence argued there was not enough evidence to prove the theory. The cause of the deaths remains unknown. THere were no marks of violence on the girls' bodies.

In a rare move, just hours after the start of deliberations, the jury asked the judge a question about whether the possibility Sorella's children died by accident had been excluded from the trial, also noting it had excluded the possibility they died of natural causes.

The judge responding they should never reveal what they're thinking behind closed doors, as doing so is a Criminal Code offence.