WETASKIWIN, Alta.- Jim McConnell thinks the lives of his two young grandsons are worth more than the sentence their mother has received for drowning the boys in a bathtub.

His former daughter-in-law, Allyson McConnell, was sentenced Monday to six years in prison. But she faces 15 months in custody because Justice Michelle Crighton gave McConnell double credit for the time she has already spent in a mental hospital. She'll be eligible for early release in 10 months.

McConnell, who is originally from Australia, drowned the boys in the family home in Millet, just south of Edmonton, two years ago when she was severely depressed, suicidal and possibly affected by alcohol and prescription drugs.

Jim McConnell stood outside the courtroom and angrily questioned the judge's decision.

"This is ridiculous. What's going to stop people from going to kill kids now?" he said. His wife and son, McConnell's former husband, sat in the hallway wiping away tears.

Crown prosecutor Gordon Hatch said he understands the family is stunned and upset, and said he is also disappointed. He had recommended a 12-year term.

"There's this desire always to try to explain a sentence as a basis for how much the children's lives are worth, and that's certainly not how we want to approach it," Hatch said afterwards.

"If the judge had imposed 15 years or 20 years or life in prison -- that's not enough for these two children."

During the trial, court heard that Allyson and Curtis McConnell were in the middle of a bitter divorce. She wanted to take their children back to her home country.

On Feb. 1, 2010, she drove an hour north of Millet to Edmonton, parked her car at a toy store and jumped off an overpass onto a busy freeway.

When police called her husband to say she was in the hospital with broken bones, he wondered where the children were and quickly drove home from work. He was horrified to find 10-month-old Jayden and two-year-old Connor floating in the tub among their plastic toys.

Their mother testified that she remembers nothing about the days before she jumped off the overpass. She also didn't know her children were dead until her mother told her while she was in the hospital. The news drove her into hysterics.

She was originally charged with second-degree murder. The Crown argued at the trial that she planned to kill her children as revenge against her husband.

But the judge ruled there was a "black hole" in the evidence and no one could know whether the depressed and suicidal woman meant to kill her boys. Court heard McConnell has a history of depression and suicide attempts that began when her father got her pregnant when she was 15.

Since her arrest, she has been under constant suicide watch while a patient at Alberta Hospital in Edmonton. She testified during the trial that she will try to kill herself again because she does not want to get well.

Her comments "bring into sharp focus the terrible price she will continue to pay for her unspeakable actions," Crighton said in her sentencing decision.

But "no matter how severely compromised Ms. McConnell was at the time, it cannot be forgotten that she took the lives of two vulnerable children who were entitled to look to her for protection."

The judge said it would be inappropriate to allow their mother to serve no additional time in custody. Defence lawyer Peter Royal had suggested she be allowed to return to her homeland a free woman.

Royal said the Canadian government has started deportation proceedings and his client could serve her sentence in Australia to be near her family.

Hatch said the deportation is probably on hold because the Crown is appealing the manslaughter conviction and is likely to appeal the sentence as well.

Crighton said she would recommend corrections officials allow McConnell to serve her sentence at the mental hospital until doctors determine she is well enough to be transferred somewhere else.

"I am concerned that if Ms. McConnell does not remain at Alberta Hospital until her physicians consider it appropriate to be transferred, the sentence I have imposed will do no more for her than prolong her inevitable demise," said the judge.

Hatch added that the woman is still the subject of a mental health warrant, so it is unlikely that she will be released when she completes her sentence. She will have to remain under psychiatric care until she is no longer considered a danger to herself or others.

McConnell showed no emotion during the sentencing, sitting quietly as she had throughout the trial. When asked by the judge if she had anything to say, she shook her head and answered simply: "no."

Crighton acknowledged the intense emotion of the case and the victim impact statements given to the court by Curtis McConnell and his parents.

The judge said no one who heard them will soon forget the anguish of Audrey McConnell, the boys' paternal grandmother, who as she talked about how she had one day cleaned her patio doors and realized too late that she was wiping away one of the children's sticky fingerprints. She cried for days knowing there would be no new ones.

"It is said that the art of living lies in a fine mingling of letting go and holding on," said the judge. "So it will be for the McConnell and Meager families."