GWINNETT, Ga. — A Gwinnett County mother concerned and confused family members by saying she'd promised her children to an "evil force" to bring back her recently deceased father. She was to "put to sleep" everyone in her house. Days later, Isabel Martinez stabbed her husband and five children, according to a newly released investigator's report obtained by 11Alive's Joe Henke.

Only one child survived the attack.

The report offers new details into the unsettling 2017 crime, for which Martinez is now serving a life sentence. They include how her husband, Martin Romero, woke up during the attack and pleaded with her “please don’t do this.”

Martinez’s case drew notoriety when she acted erratically in court – smiling, giving a thumbs-up and performing exaggerated prayer-like motions – and said she had felt a “devil-like spirit” during a family vacation to Savannah days before the attack.

Before her father died, she was by all appearances a "devoted" mother, family members said.

But the investigator’s report outlines how those around her had been worried about her state of mind in the weeks after the passing of her father in June 2017.

Martin Romero’s cousin, Griselda Romero, told investigators she had heard Martinez say she would bring her father back “by any means possible” and was “waiting for a signal” to “do his will.” She said she had promised her children to an “evil force.”

Yohanna Bucio, Martin Romero’s niece, said Martinez had made statements about wanting to offer her children to God in exchange for bringing her father back. Martinez’s niece, Edith Romero, told investigators that four days before the murders, she told the family she was going to “put to sleep” everyone in the house.

Martin Romero’s brother, Orlando Romero, said the husband had taken Martinez to a doctor who had prescribed her anti-depressants. Her husband apparently gave it to her out of fear she would attempt to overdose, and during a search officers found a medication typically used for “major depression.”

READ MORE: Mother felt 'devil-like spirit' days before family massacre 

Martinez herself told police she went to a priest two weeks before the attack and told him there were “bad people chasing her.” The priest told her she was sick and it was all in her head.

At the crime scene, Bibles were placed on top of Martin Romero and by the children, who were all left together on the same bed.

The lone survivor of the attack told investigators she saw her mother stab her sister, Dacota, and her brother, Martin Jr. The mother told her daughter they were going to the “religious clouds,” she said.

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The surviving child disturbingly described how the first child she began stabbing, Axel, woke up, but she “squeezed his nose shut and he suffocated,” according to the report.

She told police her sister Dacota woke up and said, “No, mommy, no!” She also suffocated her, as well as the rest of her children except for Diana.

►READ MORE: Survivor of family massacre: Mother told her she was going to see Jesus

Isabel Martinez admitted killing her husband and children, according to the report, telling investigators, “Soy cupable de todos los cargos,” and, “Yo no soy inocente,” – “I am guilty of all the charges,” and, “I am not innocent,” in Spanish. The report said she also “wanted salvation for her whole family and to go to the other life” and believed what she did was correct.

She told detectives she loved her family with “all of her heart,” and, in her 9-1-1 call on the day of the attack, said she thought she and her family were going “to the heavens.”

ANOTHER 11ALIVE STORY: Sophie's Nightmare: How a Georgia mother allowed her boyfriend to impregnate her 10-year-old 

During the interview, detectives had to end it when Martinez began to have “trouble staying in the present mentally,” and, one detective noted, she displayed a “distinct change in her mental clarity from the beginning of the interview.”

According to authorities, Martinez is eligible for parole in 30 years - but if she is ever granted a release, she would then go into federal Immigration and Customs Enforcement (ICE) custody for originally being in the country illegally.

She is currently held at an undisclosed mental health facility. Officials there will determine if she is ever fit to enter a general prison population.

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