Eric Sweeney enters Merrimack County Superior Court in Concord, New Hampshire, on Friday, August 15, 2025, to enter a naked guilty plea to second-degree murder of his sister-in-law, Kassandra Sweeney, and his nephews, 4-year-old Benjamin Sweeney and 23-month-old Mason Sweeney, in August of 2022. Sweeney's sentencing will be in October.

Tears welled in Savana Hammond’s eyes as Eric Sweeney walked into the courtroom and took his place beside his lawyers, his hands bound by handcuffs, his tie and white dress shirt crisp.

Even so, Hammond maintained her composure. She knew the 19-year-old defendant too well.

She knew she was looking at the face of the man who had stolen the lives of her best friend’s sister, Kassandra Sweeney, and Kassandra’s two little boys, 4-year-old Benjamin and 23-month-old Mason.

All three victims were shot and killed in their Northfield home in 2022.

Three years later, on Friday in Merrimack County Superior Court, Sweeney stood before the judge and pleaded guilty to the three counts of second-degree murder. He also pleaded guilty to falsifying evidence.

Just hours before Kassandra and her sons were killed, videos on her phone captured a scene of ordinary family life, said Bethany Durand, an attorney with the New Hampshire Attorney General’s office.

Sweeney was 16 at the time of the murders and was living in the home under Kassandra’s guardianship and that of her husband, Sweeney’s brother Sean.

Durand said the clips show the “family was having a normal morning with the boys, playing and laughing with Kassandra while helping her create a video to send to their dad.”

In court on Friday, Sweeney agreed to have no contact with any members of Kassandra’s family, including his brother Sean. Sweeney is also prohibited from having any unsolicited contact with members of his own family except for his mother.

Savana Hammond, best friend of murder victim Kassandra Sweeney’s sister, reacts as the prosecution describes the events of the day Kassandra and her sons, 4-year-old Benjamin Sweeney and 23-month-old Mason Sweeney, were shot by Eric Sweeney at his naked plea to second degree murder at Merrimack County Superior Court on Friday, August 15, 2025. Sweeney’s sentencing is scheduled for October.

Rows of the Sweeneys’ family members and friends sat in the courtroom as Durand recounted the day’s events in detail, from the dinosaur costume Benjamin was wearing when his body was found to Sweeney’s suggestion to his brother that an intruder might have been responsible for the killings during a home invasion.

Many reached for tissues, bracing themselves to hear the story of the lives lost. Some shook their heads in disbelief, while others sat in stunned silence, frozen and motionless. 

Every time Benjamin or Mason’s names were spoken, Hammond’s fingers clenched crumpled tissues tightly and pressed them to her face as it turned red. She could not hide her grief.

Autopsy results confirmed that all three victims died from a single gunshot wound to the head.

If Sweeney had not pleaded guilty on Friday, a trial would have taken place next month, with several witnesses — including his brother Sean — expected to take the stand and recount in even greater detail the events leading up to the triple murder. 

A sentencing date has been set for October 3 at 9 a.m. at the Merrimack Superior Court, where Sweeney could face life sentences for each of the murder charges.

Gopalakrishnan reports on mental health, casinos and solid waste, as well as the towns of Bow, Hopkinton and Dunbarton. She can be reached at sgopalakrishnan@cmonitor.com