The woman accused of knifing a mom changing her baby inside the Macy’s Herald Square bathroom had walked out of a mental institution in Massachusetts before ending up in a New York psych ward, where she stayed until the morning of the attack and hoped never to return, prosecutors said Saturday as more details were released on the violent, random assault. When questioned by police after Thursday’s assault, Kerri Aherne admitted she has spent most of her adult life in mental hospitals. During the summer of 2024, she walked out of her mental hospital in Massachusetts on a temporary leave pass and hopped an Uber to New York. “(She) said she could not tolerate hospitals any longer and wanted to go to prison rather than be returned to a hospital,” Manhattan Assistant District Attorney Paul Barker said at Aherne’s arraignment late Friday. Aherne got her wish on Thursday when cops arrested her on two counts of attempted murder, assault, weapons possession and endangering the welfare of a child for repeatedly stabbing a 39-year-old tourist from California holiday shopping at Macy’s Flagship store on Thursday afternoon. The Massachusetts native had purchased the kitchen knife at Macy’s moments before the 3 p.m. attack in the seventh-floor public bathroom, officials said. The victim, a civilian employee for the Los Angeles County Sheriff’s Department, was changing her 10-month-old baby girl when Aherne crept up behind her and attacked. The woman told police that she was focusing on her child when she felt a sharp pain in her back, a police source with knowledge of the case said. A moment later, she realized that Aherne had stabbed her. In a desperate attempt to protect her baby, she whirled around, confronted Aherne and grabbed the knife in the stranger’s hand. She forced Aherne, 43, to the ground and subdued her as store security was called. During the close-quarters scuffle, the woman’s child fell off the changing table, but only suffered a small bump to her head. The Macy's flagship store is seen in New York's Herald Square, Tuesday, May 11, 2021, in New York. (AP Photo/Mary Altaffer) While it was first reported that the woman’s husband, a Los Angeles County sheriff, had helped apprehend the attacker, cops said Saturday that he was in the store but didn’t realize what had happened until the threat had ended. Aherne stabbed the woman twice in the back, cops said. EMS took the mom to Bellevue Hospital, where she needed stitches to close the wounds. “She is out of the hospital and she and the baby are in stable condition,” the victim’s cousin, who wished not to be named, told the Daily News Saturday. The victim’s family still can’t believe what happened, she said. “They still have to process it,” she said. “It’s traumatizing.” On Friday, Aherne sat in a holding cell in Manhattan Criminal Court and “didn’t say a word” to anyone, a source with knowledge of the case said. “She didn’t seem crazy at all,” the source said. When she finally saw a judge, Aherne, who at times appeared confused, again reiterated that she didn’t want to be re-hospitalized. “I am what? What does that mean?” Aherne asked when she was told she was being remanded to custody. “I don’t want to go to another hospital. They didn’t help me at Manhattan Psychiatric Center.” Aherne is facing up to 25 years in prison for the attack. Her attorney, Kevin Sylvan, declined to talk to reporters at her arraignment. A call to Sylvan on Saturday was not returned. “This city is a disaster,” City Councilman Robert Holden (R-Queens) said on X about the Macy’s attack. “Progressive social experiments gutted public safety and turned New York into a dumpster fire. Families should not live in fear. We need real leadership now.” Prosecutors said Aherne was arrested in her hometown of Tewksbury, Mass., back on June 23, 2018, for posting threats on Facebook about killing Sen. Elizabeth Warren. She also said she was planning to get a gun and shoot someone at a local police station. After leaving the mental hospital in Massachusetts in summer 2024, Aherne was homeless in New York before shortly becoming a patient at the Manhattan Psychiatric Center on Wards Island, where prosecutors said she had been staying “for more than a year.” She was discharged from the Manhattan Psychiatric Center on Thursday morning, just hours before the attack, prosecutors said. After she wandered into Macy’s, she bought the knife and looked for someone to kill, claiming that “the voices in her head told her she had to kill someone or she would be killed,” Barker said. It was not immediately disclosed how Aherne ended in the Manhattan Psychiatric Center or why she was discharged. Repeated calls to the center, as well as to the New York State Office of Mental Health, were not returned Saturday. The NYPD said Aherne had never been arrested in New York City before Thursday’s arrest. In her short time between hospital stays, no one had ever called 911 on the mentally ill woman, an NYPD spokeswoman said. When reached by phone, Aherne’s relatives hung up on a Daily News reporter. Struggling with mental illness most of her life, the Bay State native was declared an incapacitated person in the last decade and relatives were named her guardians, according to published reports citing court documents. Thursday’s attack left shoppers at the 34th St. department store rattled, with some thinking twice of using the bathroom in the historic department store. “I did not use the seventh-floor bathroom because of that,” Queens resident Oishe Tawhid told The News early Friday evening as she changed her 3-year-old’s diaper in her baby carriage in the store’s frigid entrance vestibule. A friend who works at the department store told Tawid, 27, about the attack. She usually likes to change her baby in the bathroom, but thought twice about it Friday. “There should be more security, especially around the restrooms,” she said. “This shouldn’t happen to anyone. I feel so sorry for that lady.” “We are deeply saddened about the incident that took place today as the safety of our customers and colleagues is our top priority,” a Macy’s spokesman said in a statement. “We kindly defer any further questions to the local authorities.” ...read more read less