Leslianette Quintana-Betancourt was 25 when she was killed inside the Pleasantville home she shared with Boris Lainez-Rosales.
PLEASANTVILLE, N.J. — Leslianette Quintana-Betancourt was preparing for motherhood when prosecutors said her live-in boyfriend beat her to death with a baseball bat inside their Atlantic County home.
The court case now centers on Boris Lainez-Rosales, 28, who has pleaded guilty to first-degree murder. The public memory of Quintana-Betancourt, 25, also remains part of the story. Friends described her as kind, happy about becoming a mother and known for a smile that brightened a room.
Quintana-Betancourt’s name entered court records after a December 2024 emergency call from the home she shared with Lainez-Rosales in Pleasantville. She was found at the bottom of a staircase after Lainez-Rosales told authorities she had fallen. Prosecutors later said that story was false. In court, Lainez-Rosales admitted that on Dec. 2, 2024, he assaulted Quintana-Betancourt, his pregnant domestic partner, with a baseball bat at the home, causing her death. The plea ended the need for a trial but did not erase the sequence of events investigators said they uncovered inside the house.
The medical and investigative details were severe. Police said Quintana-Betancourt had blunt-force injuries to her face, arms and abdomen. She also had a ruptured placenta, and her unborn child did not survive. Investigators said the body smelled of bleach when first responders found her. The stairwell where she was placed did not show blood stains, according to the affidavit cited in the case. Those facts led police away from the fall report and toward a homicide investigation. Prosecutors later said Lainez-Rosales had staged the scene to make the killing look like an accident.
Before the 911 call, a witness in the home heard Lainez-Rosales and Quintana-Betancourt arguing from about 9:30 p.m. to 11 p.m., according to court records. The witness went downstairs to see what was happening. Lainez-Rosales escorted the witness back upstairs and said everything was fine, the affidavit said. Later, he came upstairs and used the witness’s phone to call 911. That witness account placed the couple in conflict before the emergency call and gave investigators a timeline that began hours before police reached the home.
Friends and relatives mourned Quintana-Betancourt online as a daughter, sister, aunt and friend. One friend wrote that she had been happy about becoming a mom and happy about the new journey ahead. Another remembrance described her as sweet and kind. Those memories sit beside the official record, which names her as the victim of a domestic killing and the pregnant partner of the man who admitted causing her death. Prosecutors have not released a public account of what the couple argued about. They also have not publicly described a motive for the attack.
Investigators said the home showed signs of what happened after the assault. They found bloodstains in the couple’s basement living area and on the walls. They also detected the smell of bleach throughout the apartment and said there was evidence of attempts to clean biological material. In the backyard, police found a baseball bat with bloodstains on it. In Lainez-Rosales’ car, they recovered a trash bag with possible hair attached. The evidence supported the state’s claim that the death scene had been moved and cleaned before police arrived.
Lainez-Rosales was indicted in February 2025. Local reports said the initial charges included murder, tampering with evidence and possession of a weapon for an unlawful purpose. On May 19, 2026, he pleaded guilty to one count of first-degree murder in Atlantic County. The plea agreement calls for a recommended sentence of 30 years in New Jersey State Prison without the possibility of parole. The Atlantic County Prosecutor’s Office said Executive Assistant Prosecutor Rick McKelvey represents the state. The Pleasantville Police Department and the prosecutor’s Major Crimes Unit handled the investigation.
The sentencing hearing is scheduled for July 31, 2026, before Superior Court Judge Joseph A. Levin. At that hearing, prosecutors are expected to ask the judge to impose the 30-year term called for in the plea. The defense will have an opportunity to address the court, and the court may also hear victim impact statements. The plea means guilt is no longer the issue before the judge. The remaining public proceeding will focus on punishment and the formal entry of judgment.
The case has drawn attention because the victim was pregnant, because the unborn child also died and because investigators said the first report to police tried to turn a killing into a fall. The official record gives the legal outcome. The tributes give another part of the record: Quintana-Betancourt was a young woman whose friends said she was looking forward to becoming a mother before her life was cut short inside her home.
Lainez-Rosales remains scheduled to return to court July 31. Until then, the case stands on a guilty plea, a recommended 30-year prison term and a sentencing hearing still to come.
Author note: Last updated June 21, 2026.