Nicole Virzi, a 32-year-old doctoral candidate in a joint program at San Diego State University and UC San Diego, pleaded guilty Wednesday, Oct. 28 to third-degree murder for killing her best friend's 6-week-old son in Pittsburgh in 2024.

Allegheny County Common Pleas Judge Jill E. Rangos sentenced Virzi to 35 to 80 years in prison, according to NBC San Diego. Virzi also pleaded guilty to aggravated assault and endangering the welfare of children, WPXI reported.

Virzi had faced the death penalty on a first-degree murder charge before the plea deal.

The case dates to June 2024. Virzi had flown from San Diego to Pittsburgh to visit her best friend, Savannah Roberts, and Roberts' newborn twin sons, Leon and Ari Katz, according to the San Diego Union-Tribune. On June 15, 2024, the twins' parents discovered injuries on Ari and rushed him to a hospital. Virzi offered to watch Leon while they were away.

Just after 11:15 p.m., Virzi called 911 and claimed Leon had fallen from a baby bouncer, the Union-Tribune reported. Leon was taken to a children's hospital, where he died. He had suffered a skull fracture and brain bleeds.

Investigators determined the injuries could not have resulted from a short fall and took Virzi into custody, according to NBC San Diego. The criminal complaint stated Leon's death was caused by blunt force trauma to the head and was ruled a homicide.

Authorities also determined that the injuries to Ari that sent his parents to the hospital had been inflicted by Virzi, according to NBC San Diego.

Prosecutors said Virzi told police she "always had a compulsion she could not control to harm kids," according to NBC San Diego. TribLive reported that defense attorney Tina Miller outlined Virzi's previous diagnoses of anxiety, depression and obsessive-compulsive disorder (OCD), and said her client had been in mental health treatment since age 9.

Deputy District Attorney Emma Schoedel told the court the plea was made in part to honor the wishes of Leon's parents, who did not wish to endure a trial, TribLive reported.

Roberts, Leon's mother, wrote in a letter to Judge Rangos that Virzi's actions "fundamentally changed me as a person."

"One of the most enduring impacts of Nicole's crimes is that my own self-confidence is forever shattered, and I'll never forgive myself for failing to protect my babies from this monster," Roberts said, according to TribLive.

The family said surviving twin Ari is doing well. Roberts wrote that he "has grown into the most caring, loving friend to those around him," according to the Los Angeles Times.

When given the chance to speak during the Oct. 28 hearing, Virzi declined, TribLive reported. She stood facing the judge with her eyes closed and showed no visible reaction as family members delivered victim impact statements.

Phil DiLucente, a criminal law attorney and legal analyst for WPXI, said Virzi must serve the full 35-year minimum before she becomes eligible for parole. He called it "highly unlikely" a parole board would ever release her, NBC San Diego reported.

Virzi has been held at the Allegheny County Jail since her arrest June 16, 2024, according to TribLive.