Family of Five Tragically Dies After a Long-Awaited Reunion — The Only Survivor Is a One-Year-Old Baby

A quiet neighborhood in Buenos Aires became the site of a devastating loss after an international family reunion ended due to a quiet household danger.

On July 1, 2025, five relatives were found dead inside a home in the Villa Devoto neighborhood of Argentina's capital after reportedly inhaling carbon monoxide. The victims had reunited just one day earlier, turning what should have been a joyful visit into a fatal tragedy. Now, the survival of a one-year-old boy has drawn national concern and launched an urgent investigation.

The deadly incident unfolded inside a two-story residence at 3768 Sanabria Street, located between Pedro Morán and Ricardo Gutiérrez, just one block from the Villa Devoto train station in Buenos Aires.

A concerned relative contacted emergency services after losing communication with the family. Police and other first responders rushed to the scene. Upon entry, firefighters ventilated the property, and personnel from SAME, the country's emergency medical care system, confirmed five fatalities.

On the ground floor, they found the bodies of 43-year-old Andrés De Nastochnike, his 40-year-old French partner, Marie Camille Lalanne, and their four-year-old daughter, Elisa De Nastochnike Lalanne.

In a separate room, their one-year-old son, Milo De Nastochnike Lalanne, was discovered alive, though showing signs of carbon monoxide exposure. He was immediately taken to Zubizarreta Hospital and was later transferred to Ricardo Gutiérrez Children's Hospital for further care.

On the upper floor of the house, police located the bodies of Demetrio De Nastochnike, 79, and Graciela Leonor Just, 74. They were the parents of Andrés and three other children, Maia, Alejandro, and Sergio De Nastochnike, and longtime residents of the home.

Just one day earlier, the elderly couple had welcomed their son, his partner, and their grandchildren, who had traveled from Genoa, Italy.

The arrival was documented by one of Andrés's brothers on now-private social media, with photos showing the family's emotional reunion at Ezeiza International Airport.

A day later, Maia grew concerned that she couldn't get in touch with her family and went to the house. She fainted from the effects of the gas after opening the door, but eventually managed to call the authorities.

The De Nastochnikes were a family with deep community roots. According to Devoto Magazine, they had lived in the neighborhood for decades and were widely admired.

"We can't believe it. They were good people, very devout, and always present in the neighborhood's activities," said a neighbor.

Authorities from the National Criminal and Correctional Prosecutor's Office No. 48, led by Dr. Rosende and Secretary Dr. Rosasco, are overseeing the investigation into this tragedy.

Preliminary findings from firefighters suggest a "99 percent certainty" that carbon monoxide inhalation was the cause of death.

Additionally, the Forensic Police support this hypothesis, and technical assessments of the home's gas system and appliances are ongoing. Investigators have confirmed that multiple procedural measures are being carried out to determine how the gas accumulated inside the residence.

Meanwhile, the family's background is rich with historical and academic significance. Demetrio was born in Belgium and had a degree in Business Administration from the University of Buenos Aires, a master's in Education from the Catholic University of Salta, and a specialization in the management and evaluation of higher education institutions from the National University of Tres de Febrero.

He served as a professor of economics and director of the Business Administration program at the National Military College and contributed to the Revista Digital Universitaria.

His ancestry traces back to Russia. As reported by Russia Beyond, Demetrio was a descendant of a servant of the Tsar who received a noble title after sustaining a sword wound to the face during a battle with the Tatars in 1327.

The family fled Russia during the 1917 Revolution, passed through Yugoslavia and Belgium, and eventually settled in Buenos Aires. Demetrio's father founded Magnifico, a factory that produced toys and collectible toy soldier figures.

"Argentina is our adopted homeland. It gave us peace and education; we live very well here," Demetrio once said. He also noted that a street and a House-Museum still bear the family name in Moscow's historic center.

Meanwhile, his son, Andrés, was a software engineer and had spent the past decade living and working in Italy. According to his LinkedIn, he was employed by ManyDesigns srl in Genoa and had contributed to projects for Leonardo Company.

His professional history also included roles at Snoop Consulting in Buenos Aires, SQLI in Lyon, ElsagDatamat in Genoa, and OpenJaw Technologies in Dublin. He earned his engineering degree in computer software from the Pontificia Universidad Católica Argentina in 2006.