This story discusses suicide. If you or someone you know is having thoughts of suicide, please contact the Suicide & Crisis Lifeline at 988 or 1-800-273-TALK (8255).

When Theresa DeLucia, a 95-year-old mother of four from New York’s Long Island, died last month, she had already laid out her wishes in a last will and testament more than a decade ago.

The 2007 document, however, may have played a role in her youngest son’s shooting rampage, which killed his three siblings and a niece in a murder-suicide.

Joseph DeLucia stood to gain one-fourth of the value of the home’s sale as well as a quarter of the rest of his mother’s estate. Zillow estimates placed the property value at almost $900,000.

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DeLucia lived with his mother up until her death, but in her will, she wrote that “I direct any member of my family who may be living in such home at the time of my death to vacate same to facilitate such sale.”

She also empowered her oldest son, Frank, to enforce the provision.

Apparently fearing that he would be left homeless, Joseph massacred the rest of his family.

Read Theresa DeLucia’s last will and testament

“[In] 41 years, it is probably one of the most horrific scenes I’ve ever seen,” Nassau County Police Commissioner Patrick Ryder told reporters in a news briefing. 

He said that there were warning signs that might have prevented the slayings if they had been reported to police.

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“There was talk in that community about the distress of this shooter that had decided he did not want to leave his residence after his mom died,” he said. “There was talk in the community in the past that if you hear shots fired, don’t call the police – it’ll be too late.”

Family members gathered at the DeLucia matriarch’s home on Wyoming Court in Syosset on the morning of Aug. 25, grabbing coffee from Starbucks ahead of a planned meeting with a real estate agent to discuss selling the home, police said. The suburban neighborhood is about 30 miles east of New York City.

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A neighbor called 911 just before noon. Police found Joseph DeLucia, 59, dead outside, near a shotgun on the grass.

Inside, they found Joanne Kearns, a 69-year-old sister who lived in Tampa, Florida; Frank DeLucia, a 64-year-old brother who lived in Durham, North Carolina; Tina Hammond, a 64-year-old sister who lived in the neighboring Suffolk County; and her daughter Victoria, 30.

Joseph DeLucia had a history of mental illness but no significant criminal record beyond a drunken driving stop decades ago, according to authorities. However, under New York’s red flag law, police could have taken away his shotgun, police said.

Nassau Detective Capt. Stephen Fitzpatrick said the killer believed he was being cut out of the will and would have been thrown out on the streets when his siblings sold the home. 

“Because of that perception, he decided that day to get a loaded Mossberg shotgun, 12-gauge, approach them in the rear area of the house, and from the kitchen fire 12 shots, striking all four of them multiple times,” he told reporters at the briefing.

Neighbors heard him on the front lawn shouting before DeLucia fired a final shot into his own chest. A haunting final post on a Facebook page under his name shows a New York license plate reading, “DEPRSSED.”

“If anybody has somebody that they think has issues, they should be calling us,” Fitzpatrick added.

Mary Macaluso, a local realtor, told the local newspaper Newsday that she was supposed to meet the family and arrived to find the block closed off with police tape.

This story discusses suicide. If you or someone you know is having thoughts of suicide, please contact the Suicide & Crisis Lifeline at 988 or 1-800-273-TALK (8255).