WAUKESHA, Wis. -- A Wisconsin girl inspired by fictional horror character Slender Man to try to kill a classmate made a tearful apology before she was sentenced Thursday to spend 40 years in a mental institution, the maximum sentence.

Doctors who evaluated 15-year-old Morgan Geyser provided conflicting opinions at a sentencing hearing about the type of institutional care she needs and the severity of her continued hallucinations. Prosecutors wanted Geyser to spend the maximum 40 years in a mental hospital for stabbing Payton Leutner in suburban Milwaukee in 2014. 

"I just want to let [Payton] and her family know I'm sorry," Geyser said, sobbing. "I never meant this to happen. And I hope that she's doing well."

To make their case during Geyser's sentencing hearing in Waukesha County Circuit Court, they presented testimony from a doctor who said Geyser reported still hearing voices from someone named "Maggie" as recently as September.

Dr. Brooke Lundbohm acknowledged that Geyser has made significant progress over the last three years, but said she emphatically believes she is still a danger to herself and others.

"This is not a close call," she said. 

Geyser's attorneys advocated for her to be moved to a less restrictive facility with children her age and the possibility of being able to be on outings with supervision if she's well enough.

Two doctors called by the defense said Geyser no longer exhibits psychotic symptoms.

"I believe at the present time she is no more dangerous than any adolescent her age," said Dr. Kenneth Robbins.

The hearing lasted most of the afternoon and included victim impact statements. 

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