'He's in his room': Mom who led cops to 5-year-old son's body with plastic bag covering his head is going away for a long time — but not to prison

Left: Kathryn Garaas (KRTV). Right: Reign Blair (GoFundMe).

A Montana woman who suffocated her 5-year-old son to death with a plastic bag because she wanted to "save him because things would have only gotten so much worse" received a decades-long sentence — but won't be spending any time in a prison cell.

Kathryn Garaas, 40, was sentenced to 50 years in the Montana State Hospital on Wednesday after she pleaded guilty but mentally ill to deliberate homicide in June for the death of Reign Tyler Blair at their home near Whitehall, which is some 60 miles northwest of Bozeman.

Garaas' defense attorney Marisa O'Sullivan said the facility is the most appropriate place for her client.

"The best to come out of this is to get Kathryn the help she needs," O'Sullivan said, according to a courtroom report from Bozeman CBS affiliate KBZK. "The Montana State Hospital is the only place in Montana that's equipped with the tools to help treat her mental health as well as ensure the safety of the community."

District Judge Luke Berger agreed that mental health was an issue but said there was more to it than that.

"I mean, yes, mental illness is the reason that we're here. But also, the reason that we're here is a truly unexplainable darkness that I can't grasp," he said.

Berger said he wished the mental health system could have addressed Garaas' needs before she killed her son.

"We've got to fix the mental health system. We have to do that in society but this goes beyond that. This goes beyond an unacceptable level. I deal with a lot of people who are mentally ill and this is not normal, it's tragic," Berger said, per NBC affiliate KULR.

According to the Jefferson County Sheriff's Office, deputies responded on the afternoon of April 24 to the home for a medical emergency. A probable cause arrest affidavit obtained by Great Falls CBS affiliate KRTV stated the boy's father asked for a welfare check on the boy when he received a disturbing text message from Garaas.

When Garaas opened the door for deputies, she told them "he's in his room."

Deputies went to the boy's room to find a plastic bag over his head, the affidavit reportedly said. He was dead.

Garaas reportedly told cops she killed her son because she felt she had to "save him because things would have only gotten so much worse."

Colleen Much, who started a GoFundMe account on behalf of Reign's family, said in an interview with KRTV that Garaas was previously separated from the family. But Garaas had been staying with the boy and his father for weeks leading up to the murder without incident.

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"I cannot and will absolutely not pretend to claim we have even a remote understanding of the reasoning behind this, or what occurred," Much wrote in the description. "We pray for answers that may never come, and when they do, no healing will come of it."

Much called Reign a "precious, innocent, perfect, beautiful little light" who was raised by his father.

"Reign is his purpose, his love, and his life from the moment he took his first breath," Much wrote. "There are no words for the kind of strength it takes for a man to be a single father, and the life he built for Reign is one we take solace in knowing was fulfilled with love, laughter, and precious joy."