Aiden Zachary pleads guilty to fatal stabbing of boy, 15, at West Babylon party

A Syosset man, who was a minor when he fatally stabbed a 15-year-old boy at a West Babylon house party last year, pleaded guilty to the attack Thursday and will be sentenced as an adult, according to the Suffolk County District Attorney's Office.

Aiden Zachary, 18, admitted to stabbing Liam Delemo, of West Babylon, on Nov. 3, 2025, after his ejection from the party devolved into a fight, District Attorney Ray Tierney said in a news release. Prosecutors said Delemo suffered stab wounds in the arm and the abdomen. The attack severed the teenager's colon and pancreas, Newsday previously reported. He died during surgery at Good Samaritan University Hospital.

Zachary pleaded guilty on Thursday to first-degree manslaughter before acting state Supreme Court Justice Karen Kerr at Suffolk County District Youth Court in Central Islip, according to court documents. He is scheduled to return to court Nov. 4., one year after Delemo's death.

His defense attorney, Jacob Kaplan, could not be immediately reached Thursday evening.

Newsday previously reported that at about 10 p.m. on Nov. 3, 2025, Zachary, then 17, and two friends arrived uninvited to the party, which about 100 teens attended. They were soon told to leave. Video footage from the evening shows Zachary yelling at someone inside the house to “come outside” while threatening other attendees. Delemo then tackled him in the front yard. While fighting on the ground, Zachary pulled a knife from his waistband and began stabbing Delemo.

The “senseless act of violence” has “forever changed” both teens’ families, Tierney said in a statement. “This young defendant chose to escalate a dispute with a deadly weapon, resulting in the tragic death of a 15-year-old boy."

The party took place around the corner from Delemo’s home, his parents previously told Newsday. After receiving a call from one of his friends, his parents rushed to the scene and found him conscious and as “white as a ghost” on the back deck of the home, his father, Mike Delemo, said.

Since Zachary was 17 at the time, he “was charged as an adolescent offender,” a spokesperson for Tierney’s office told Newsday via email. Now 18, he “will be sentenced as an adult,” they added.