VANCOUVER, Wash. - A Clark County mother who pleaded guilty to killing her 20-month-old son was sentenced to 24 years in prison Tuesday.

Kelly Meining said she stabbed the boy to death on May 19, 2006, because she believed other people were going to kill him.

Her family told Clark County Superior Court Judge Diane Woolard on Tuesday that Meining had a long history of mental problems, including bipolar disorder, postpartum psychosis and borderline schizophrenia, that the family said were ignored until she took a kitchen knife and repeatedly stabbed her son Bryce.

Meining's husband told the judge the system had failed.

"I feel the system needs to change," Kris Meining said. "This happens all the time to mothers, you know ... and there just needs to be more attention to these people who cry for help."

But psychiatrists could not confirm Kelly Meining's mental state the morning of the murder.

Now instead of going to a mental hospital in Tacoma, Wash., she will spend her time in prison. However, she will be allowed to visit her two remaining children at the prison.