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A grandmother and her daughter meticulously planned the deaths of four children inside an upstate New York apartment before taking their own lives, believing the horrific scheme would keep them safe from 'abuse,' police revealed.

Sarah Myers, 44, and her mother, Amy Steadman, 64, are accused of orchestrating the June murder-suicide that left Myers' children - Harper, 13, Hudson, 11, and 10-year-old twins Gavin and Gracelynn - dead, according to authorities.

Investigators uncovered evidence pointing to a mass poisoning, though it has since been revealed that 10-year-old Gavin was 'repeatedly' stabbed to death with a knife.

During a Tuesday press conference, officials said a mountain of new evidence points to the mother-daughter duo deliberately planning the murders before taking their own lives - despite a handwritten confession signed solely by Steadman.

Mechanicville Police Chief Bill Rabbitt laid bare chilling new details, including text messages that allegedly showed the pair’s plot beginning on June 5, 2026 - just five days before the killings.

The texts revealed talks about 'obtaining medications, where the murders would occur and how those medications would be administered,' according to the chief.

They also detailed conversations about how the children would be brought together, what they would be told and how suspicion could be avoided before the deadly act.

A series of chilling messages were exchanged between Myers and Steadman on June 10, with one revealing that Myers instructed her mother on when the medications should be administered to begin the process.

Sarah Myers (pictured), 44, and her mother, Amy Steadman, 64, are accused of planning a murder-suicide that left Myers' children - Harper, 13, Hudson, 11, and 10-year-old twins Gavin and Gracelynn - dead

Investigators found evidence pointing to a mass poisoning, though it was revealed that 10-year-old Gavin was 'repeatedly' stabbed to death with a knife inside the Mechanicville, New York, apartment

Police said a handwritten confession signed by Steadman read that 'killing the children was the only way to keep them safe from alleged abuse in Utah'

'Sarah Myers instructed Amy Steadman that the medications should be administered between 10.30am and noon so they could be finished before a scheduled telephone call at 6pm with the children’s father,' Rabbitt said.

The chief said their plan appeared to take a turn later that morning, when 'the children failed to respond in the manner that Steadman and Myers had anticipated.'

Around the same time, Rabbitt said one of the women - without specifying which - sent the other a sinister message: 'It's not working. We need another option.'

The investigation found that Steadman had visited multiple pharmacies in the days leading up to the mass-poisoning event, the chief shared during Tuesday's press conference.

'Surveillance footage, purchase records and evidence collected through search warrants documented that Steadman obtained multiple doses of over-the-counter sleep aids and multiple medications that had been prescribed to her,' he said.

Rabbitt said those purchases became 'even more significant' in light of the disturbing text messages exchanged between the grandmother and mother.

Mechanicville Police Chief Bill Rabbitt said the pair began discussing their plot on June 5, 2026 - just five days before the killings

Police said text messages between Myers and Steadman revealed talks about 'obtaining medications, where the murders would occur and how those medications would be administered'

Text messages from June 10 revealed that Myers instructed her mother on when the medications should be administered to begin the process, police said

Internet history recovered by authorities showed 'searches about medication reactions, the effects of insulin on non-diabetics and the Utah court system,' according to the chief.

Rabbitt said later searches included 'Where is the most fatal place to be stabbed,' which returned results detailing a specific artery as well as the neck.

Gavin, who was repeatedly stabbed with a knife, suffered a defensive wound that 'indicated he attempted to protect himself during the attack,' police revealed.

The final text communication between Steadman and Myers was exchanged just after 8.30pm on June 10 - about an hour before surveillance footage captured Steadman heading to a local gas station before returning to her apartment.

A neighbor first requested a welfare check on June 13 before another was made four days later on June 17. The six family members were ultimately found dead during a third welfare check on June 23 - 13 days after they were last seen.

Chief Rabbitt said that at the time, the bodies were too badly decomposed for responding officers to immediately identify them.

The grim discovery came just days before the children were set to travel to Utah to spend the summer with their father, Brady Harmon, as the pair remained locked in an ongoing custody battle.

On Tuesday, Rabbitt told reporters that investigators discovered a handwritten confession signed by Steadman herself during a search of her home.

The investigation found that Steadman visited multiple pharmacies in the days leading up to the mass-poisoning event

The six family members were ultimately found dead during a third welfare check on June 23 - 13 days after they were last seen

The grim discovery came just days before the children were set to travel to Utah to spend the summer with their father, Brady Harmon

'In that letter, the author accepts responsibility for what occurred and states that they believed killing the children was the only way to keep them safe from alleged abuse in Utah,' the chief said.

The confession claimed that 'Sarah Myers had done everything she could and that no one would help her, and acknowledged that the events did not unfold as they planned,' he added.

Several additional handwritten notes referring to the children as 'my babies' were also found inside the apartment. Although the writings were unsigned, investigators believe they were written by Myers.

Rabbitt said the author 'expressed anger toward the Utah family court system, made allegations that she and the children had been abused while living in Utah and complained that she had been unable to obtain legal representation.'

'Amy Steadman and Sarah Myers consistently portrayed these murders as a way of protecting the children,' he said. 'Whatever they believed justified their actions, the deliberate murder of four children cannot be described as protection.'

Brady Harmon, the children’s father, has denied all abuse allegations. Last week, he told The US Sun that he and Myers married in 2015 before separating four years later - the last time he saw his children.

He described Myers as the 'culprit' rather than a 'victim,' alleging that she stabbed him in the face with a medicine dropper during an argument in 2019.

Harmon also accused his ex-wife of keeping his children away from him in an effort to maintain a sense of 'control.'

The confession letter said, 'Sarah Myers had done everything she could and that no one would help her, and acknowledged that the events did not unfold as they planned'

Harmon accused his ex-wife of keeping the children away from him to maintain a sense of 'control'

Several additional handwritten notes believed to be written by Myers were found inside the apartment, which 'made allegations that she and the children had been abused while living in Utah'

Still, he said he remained in contact with the children and had reached an agreement with his ex-wife that he would have custody from July 1 through September 1.

He last spoke with his kids on June 7, but received a text from Myers three days later saying they were sick. 'She messaged me, "Hey, the kids are sick, we'll talk to you on the 11th,"' he said.

That same day, he said his attorney sent Myers paperwork related to an upcoming custody hearing scheduled for June 29.

'I don't know if that pushed them over the edge because like, "Oh my gosh, he actually has a lawyer that's going to do his job. And we don't know a way out of this, so let's do the next best thing. He'll never have access to these kids…" and then do what they did,' he speculated.

Even before Tuesday’s press conference, Harmon said he had suspected that both Myers and Steadman were responsible for the heinous crime.

'All because they were going to spend 60 days with me. Sixty days in six and a half years. I finally get 60 days, and I get this thrown in my face,' Harmon told Spectrum News, referring to the upcoming Utah trip.

'I have been fighting for so long to be able to have access to them, fighting so long to be part of their lives and show them there’s something different,' he added.

Harmon also claimed he received 10 letters from Saratoga County Child Protective Services informing him that the agency was investigating conditions at his children’s home.

Internet history recovered by authorities showed 'searches about medication reactions, the effects of insulin on non-diabetics and the Utah court system'

In the confession letter, the author 'accepts responsibility for what occurred,' according to police

Police said the investigation remains ongoing, with detectives still awaiting the children’s final toxicology results

The last letter he got stated that Myers was being investigated for Munchausen syndrome by proxy, the father told The Albany Times Union.

Harmon said a therapist concluded at the time that Myers had been negligent in her care of the children, but determined they were not in any immediate danger.

'Nothing happened after that,' he said, noting that when he went to collect his children's belongings from Myers' apartment earlier this month, he found the unit a mess, with cat urine and feces throughout.

The cat was later rescued by Mechanicville Housing Authority management and has since found a permanent home.

Harmon also told the outlet that he does not know who contacted Child Protective Services on behalf of his children.

However, he believes officials at the Mechanicville City School District may have alerted the agency, as the letters stopped arriving after Myers withdrew the children from the district in 2024 to homeschool them.

He is now working to obtain the children’s school records.

Chief Rabbitt said the investigation remains ongoing, with detectives still awaiting the children’s final toxicology results.

He added that authorities likely will not release those findings to the public, fearing others could attempt to replicate the alleged killers’ behavior.