In the image on the left, Kacy Corso is shown (courtesy of the Suffolk County Sheriff’s Office), while the right features Christopher Millwater (from his own Facebook selfie). The backdrop is the Stony Brook Yacht Club marina, the tragic scene of the fatal stabbing on Long Island, N.Y. (sourced from Google Maps).
A New York woman faces the prospect of significant prison time after confessing her involvement in a fatal stabbing at a Long Island yacht club.
This week, 34-year-old Kacy Corso admitted guilt to manslaughter and obstructing justice concerning the death of Christopher Millwater, 52, in November 2025.
In the following month, December 2025, both Corso and her boyfriend at the time, Victor Panebianco, 32, were charged with second-degree murder for Millwater’s death. Notably, Millwater was Corso’s former partner.
Prosecutors plan to advocate for a seven-year prison sentence for Corso, thanks to her decision to provide full cooperation in the prosecution’s case against Panebianco, reported Newsday.
“She accepted responsibility,” defense attorney Christopher Gioe said outside the courtroom building in Riverhead on Wednesday. “She had a very limited role in what happened in this case.”
The incident occurred on Nov. 10, 2025, at the Stony Brook Yacht Club. Corso claims she simply drove the car that day.
During her plea hearing, she reportedly said it was only her intent to “cause serious physical injury” to her ex-boyfriend.
“What was the plan?” state Supreme Court Justice Timothy Mazzei asked Corso at one point in the proceedings.
In low tones, the woman replied: “There was no plan.”
Plan or not, Millwater was stabbed to death outside 21 Shore Road during the early morning hours, police said.
“Shortly after Corso drove into the parking lot at the yacht club, Millwater pulled in and parked next to her,” prosecutors wrote in a press release announcing the indictment. “After Corso then positioned her car in front of Millwater’s car, Panebianco allegedly exited the passenger side of Corso’s car and approached Millwater’s car. Millwater drove around Corso’s car, and towards the exit of the parking lot. Corso then allegedly drove her car into his vehicle. After the crash, Millwater exited his car and ran from the scene.”
Next, the state alleges Panebianco chased after the victim, swinging some sort of object, citing surveillance footage.
“You’re stabbing me?” the frightened man asked his killer as he was knifed through his heart and lungs, authorities said.
“Video then shows Panebianco caught up to Millwater, and while Millwater was on the ground, Panebianco allegedly threatened to kill him and yelled at him to stay away from Corso,” the press release goes on. “Corso can also be heard yelling at Millwater. As Millwater lay motionless on the ground, Panebianco allegedly kicked Millwater in the head. Panebianco then got back into Corso’s car and she drove off.”
Police found Millwater at around 3:40 a.m. and rushed him to Stony Brook University Hospital where he was pronounced dead.
The victim had “liked” one of Corso’s Facebook posts in the days before the murder, Fox News reported at the time of the indictment.
Panebianco is still charged with murder in the case and faces up to 25 years in prison. Corso is slated to be sentenced in September.
The post ‘You’re stabbing me?’: Woman pleads guilty to manslaughter for role she played in death of ex-boyfriend who ‘liked’ one of her Facebook posts days before he died first appeared on Law & Crime.