A Texas woman was convicted of capital murder and sentenced to life in prison after she was found guilty of stabbing and beheading her five-year-old daughter because she 'asked for cereal.'

Krystle Villanueva, 27, of Kyle, Texas, was convicted Thursday for the murder of killing her daughter, Giovanna Hernandez, five, in 2017.

The jury also found Villanueva guilty of aggravated assault with a deadly weapon in the stabbing of the girl's grandfather - Eustorgio Arellano-Uresti - who survived the attack.

A judge sentenced Villanueva to life in prison without parole.

Krystle Villanueva, 27, was found guilty of murdering her five-year-old daughter in January 2017 and sentenced to life without parole Thursday after a two-week trial in Texas. She appeared to be smirking or holding back laughter in her 2017 mugshot

Villanueva was arrested after police found her in her home, along with her daughter Giovanna Hernandez, five (pictured), who had been stabbed to death and decapitated

The Hays County District Attorney's Office said in a press release Thursday that during her two-week trial, Villanueva had claimed that she'd been 'under the delusional belief' that Giovanna and Arellano-Uresti 'had been replaced by clones and had to be killed to bring back her real family members.'

Villanueva was arrested at her home in Kyle - which she lived in with Giovanna's father, Refugio Hernandez, Jr., and his parents - in January 2017 after both Arellano-Uresti and Villanueva called 911.

Prosecutors said that Arellano-Uresti told the 911 operator that Villanueva, then 24, had suddenly attacked him from behind, before stabbing him in the back and head. He was then able to flee from the home.

When it was determined that Villanueva was still inside the house with Giovanna, a SWAT team and crisis negotiators were called in about a potential hostage situation.

Villanueva (right with Giovanna) lived with Giovanna's father and his parents in Kyle, Texas

Villanueva (pictured at left in a recent mug shot and at right in an undated image) was also found guilty of aggravated assault with a deadly weapon for stabbing Giovanna's grandfather, Eustorgio Arellano-Uresti

During the incident, Villanueva (right with Giovanna) called 911 and told the operator that she had killed her daughter because she 'asked for cereal'

Prosecutors said that while police were surrounding the house, Villanueva also called 911, telling the operator that 'she had killed her daughter because 'she asked for cereal,'' and admitting that she had stabbed Arellano-Uresti.

The SWAT team then broke into the house where they found an apparently freshly showered Villanueva naked in the front room.

They then found Giovanna in a bedroom. She had been stabbed to death and decapitated.

Eustorgio Arellano-Uresti (pictured) survived having been stabbed by Villanueva

Villaneuva was arrested and taken to the hospital, where blood tests revealed she had alcohol and marijuana in her system.

A mugshot taken at the time of her arrest in 2017 showed Villaneuva appearing to smirk or stifle laughter while looking at the camera.

During the trial, Villanueva's defense team did not deny that she had killed her daughter and attacked Arellano-Uresti, but they urged the jury to find her not guilty by reason of insanity.

Villanueva's lawyer, Carlos Garcia, suggested that she might have Capgras Syndrome, also known as 'imposter syndrome,' according to the San Marcos Record.

They presented evidence that showed that she had been treated for mental problems.

An affidavit taken at the time of her arrest revealed that Arellano-Uresti alleged Villanueva had used drugs, alcohol and marijuana, while friends told KXAN that she had had struggled with drug use in the past and had gone to rehab and 'came out good.'

During the trial, prosecutors said that the treatment Villanueva was receiving coincided with prior drug abuse and that the symptoms she was described as having during the trial had never been observed by her prior to or after her arrest.

During her trial, Villanueva's defense team said she might have impostor syndrome and that she believed Giovanna (pictured at right with Villanueva) and Arellano-Uresti had been replaced by clones and needed to be killed so the originals could be returned

Villanueva's defense team urged the jury to find her not guilty be reason of insanity

The Texas home where a SWAT time found Giovanna's body, stabbed and decapitated

Prosecutors said that a psychiatric expert called by the defense admitted on cross-examination that the use of marijuana could exacerbate existing mental conditions and interfere with treatment.

Villanueva's lawyer, Carlos Garcia, told The Associated Press Friday that he was disappointed with the verdict and that she had suffered from psychosis for many years.

In addition to being sentenced to life in prison without parole fo r capital murder of a child under ten, Villanueva was also given a 20 years sentence for the aggravated assault with a deadly weapon against Arellano-Uresti.

'A case like this leaves an unforgettable mark on everyone involved, especially the child's family,' Hays County Criminal District Attorney Wes Mau said in a statement.

'Every law enforcement member who worked on this case will forever be traumatized by what Ms. Villanueva did to her innocent daughter.'