Glamorous 29-year-old PhD student 'who tortured a friend's baby to death while babysitting him' is warned she faces the ultimate penalty if convicted

A glamorous graduate student faces execution if found guilty of murdering her friend's six-week-old son while she was babysitting him, prosecutors say.

Nicole Virzi, 29, was charged with murdering 6-1/2-week-old Leon Katz while she was babysitting him at the family's Pittsburgh home in June.

Police allege she is responsible for a skull fracture and multiple brain hemorrhages, which were discovered during a CT scan. She is also accused of injuring Leon's twin brother Ari, who survived.

Court documents obtained by WPIX show that the Allegheny County District Attorney's Office is seeking the death penalty for Virzi.

The file setting out the reasons for demanding the death penalty states: “The accused committed the murder in the course of committing a crime. The crime was committed through torture.”

Police claim she is responsible for Leon's skull fracture (pictured) and several brain hemorrhages that were discovered during a CT scan.

Leon's alleged killer was a “trusted friend” of the babies' parents, Ethan Katz and Savannah Roberts. (Pictured: Baby Leon shortly after his birth in May 2024)

“The defendant has already been convicted several times for serious crimes in which he used or threatened violence. The victim was a child under the age of 12.”

Further details about those previous convictions were not disclosed. A review of public records on Virzi revealed only details about the charges she faces in Leon's murder.

Virzi was a “trusted friend” of the babies’ parents, Ethan Katz and Savannah Roberts, who looked after the twins while they were away on college vacation.

Her father, Peter J. Virzi, is a leading cardiologist associated with Mt. Sinai Doctors in Manhattan and board-certified by the American Board of Internal Medicine.

The person accused of murder continued to care for little Leon while his parents were at UPMC Children's Hospital of Pittsburgh with his twin brother Ari after Virzi said he discovered an injury in his groin area, police said.

She told police that she went into the kitchen to get a bottle for the baby when she suddenly heard screaming.

When she returned, she said the baby had fallen out of the bouncer. Then she called 911.

“The injuries sustained by both (twins) are consistent with child abuse as they are inflicted injuries and are neither natural nor accidental,” a doctor told investigators, according to court documents.

Virzi was a “trusted friend” of the babies' parents, Ethan Katz and Savannah Roberts (pictured), who looked after the twins during their college vacation

Prosecutors in Pennsylvania are seeking the death penalty for Virzi, who denies any wrongdoing

Pictures taken just days before the tragedy show the twins with shining eyes standing side by side in rompers with their names embroidered on them

The suspect's father was identified as Peter J. Virzi, a leading cardiologist associated with Mt. Sinai Doctors in Manhattan.

Virzi has denied any wrongdoing and her lawyer maintains her innocence. She is charged with murder, child endangerment and aggravated assault.

The police are still unable to find out a motive for this cruel crime.

In a video posted a few days before the doctoral student allegedly killed her friend's baby, she is seen discussing a paper she had written on depression in women.

In the video, published June 13 by the scientific journal Heart and Mind, Virzi wears a white blazer and appears eloquent as she delves deeply into how physical symptoms of depression can put women at risk for heart disease.

A GoFundMe page for the devastated couple says Leon “tragically died under horrific circumstances” and that a “trusted family friend” has been arrested.

“Leon will always be remembered as a happy, smiling and fun little boy. His untimely and tragic death has deeply affected the Pittsburgh community,” the fundraising page said.

In pictures taken just days before the tragedy, the twins were seen standing side by side, bright-eyed, in rompers with their names embroidered on them.