04/04/2012 09:30 am ET Updated Apr 04, 2012

Amy Kern's Insanity Plea Accepted After She Killed Two Family Members

A South Florida family is in shock after a judge on Monday deemed Amy Kern -- who killed her own kin on a bloody rampage -- not guilty by way of insanity.

In February 2009, Kern beat her grandmother to death with a tire iron and shot her aunt's boyfriend dead in a killing spree apparently set off by her untreated schizophrenia and bipolar disorder, WPTV reported.

Relatives gathered at a West Palm Beach courthouse wearing shirts bearing the victims' faces.

"I hope to God that she rots in hell -- I mean it from the bottom of my heart," said Harriet Curles, the sister of victim William Chapman, to the judge.

Psychiatrists hired by both sides of the case found that Kern was insane at the time of the crime, according to CBS 12.

Detectives say that Kern drove from Georgia to Port St. Lucie three years ago, stole her fathers gun and shot Chapman to death in Palm Beach Gardens. Then she went to her grandmother's home and bludgeoned her to death. Cops later found Kern babbling about Jesus.

Judge Jeffrey Colbath acknowledged on Monday the pain that the family was going through. Kern may not be guilty of murder, but she's not free either, he said.

"She will be locked up," the Palm Beach Post quoted him as saying. "She will be in a secure facility, a prison for the mentally insane at least for the foreseeable future, perhaps for the rest of her life."

Lawyers said that Kern had been diagnosed as bipolar and schizophrenic in her 20s and never received proper treatment. She'll be up for a sanity re-evaluation every six months to a year.