The Alberta father of two young sons killed by their mother in February 2010 wept as the judge sentenced Allyson McConnell on Monday to 15 more months in custody.

Curtis McConnell cried outside the Wetaskiwn courthouse after Justice Michelle Crighton sentenced McConnell's former wife to six years, but giving her two-for-one credit for time already served.

According to Crighton, that leaves McConnell with 15 months left to serve and eligible for parole in March 2013.

The sentence will "punish her, but also afford her the best opportunity "to deal with psychological issues," said Crighton.

The boys' grandfather Jim McConnell called the sentence "absolutely ridiculous" and a "bloody joke."

"Is that all the boys' lives are worth?" he said outside the courthouse. "This is crazy."

Crown urged to appeal sentence

He urged the Crown, which is already appealing the manslaughter conviction, to appeal the sentence.

While prosecutor Gordon Hatch called the sentence disappointing, he noted that should the Crown's appeal be successful, the sentence would be thrown out.

Curtis and Allyson McConnell are shown with sons Connor and Jayden in an undated photo. ((Facebook))

Crighton recommended McConnell serve her time at the Alberta Hospital until she is ready to be transferred.

McConnell was convicted in April after drowning sons Connor, 2, and 10-month-old Jayden in the bathtub of their Millet, Alta., home during a bitter divorce battle with her husband.

Hatch wanted McConnell to serve 12 years, with three years credit for the time served in a psychiatric hospital.

During the trial, he argued McConnell killed her boys at the family home as revenge against her husband, who had refused permission to let her return to her native Australia with the boys.

But the defence said McConnell's mind was so clouded by alcohol, sleeping pills and severe depression that she could not have formed the intent required to convict her of second-degree murder.

Lawyer Peter Royal believed she should not have to serve any more time in custody.

Royal is hoping McConnell will eventually be allowed to go back to Australia to serve out her sentence.

Last month, the Crown filed notice it is appealing McConnell's manslaughter conviction, believing McConnell should have been convicted of second-degree murder.

It believes Crighton erred in the analysis of expert evidence and in the consideration of whether McConnell could form the intent to kill her sons.