A brave 10-year-old girl realized her mother and grandmother were slowly poisoning her and her four siblings just before they were killed in a horrific murder-suicide, officials said. 

Gracelynn Harmon, her twin brother Gavin Harmon, 10, and her two older siblings, Hudson, 11, and Harper, 13, were found dead inside their grandmother Amy Steadman’s apartment in Mechanicville, New York, on June 23. 

The children’s mother, Sarah Myers, 44, and Amy, 64, were found dead alongside them after killing themselves, police said. 

Gavin suffered ‘multiple sharp force injuries,’ and his brother and sisters showed signs of being poisoned, Mechanicville Police Chief William Rabbitt said during a press conference on Tuesday. 

According to Rabbitt, Gracelynn was onto her mother and grandmother and knew that they were poisoning her and her siblings, messages uncovered by police revealed. 

‘Why would you do that? You both won’t let me puke,’ Gracelynn, who also went by Gracie, said as she complained of increased pain in her stomach.

Later that night, Amy told her daughter: ‘Gracie is aware,’ and the two of them continued to communicate about their sinister plot. 

Investigators recovered electronic files, including text messages between Sarah and Amy that explained how the mother and daughter would get medication and kill the children to ‘protect them,’ Rabbitt said. 

Gracelynn Harmon (far right), her twin brother Gavin Harmon (second from right), 10, and her two older siblings, Hudson (second from left), 11, and Harper (far left), 13, were found dead inside their grandmother Amy Steadman’s apartment in Mechanicville, New York, on June 23

The children’s mother, Sarah Myers (pictured), 44, and Amy, 64, were found dead alongside them after killing themselves, police said

He confirmed that Sarah and Amy committed the murders so they could keep the children away from their father, Brady Harmon. 

Sarah accused him of domestic violence, but he has denied any wrongdoing and has not been charged with a crime.

She allegedly wanted everyone to be dead before her 6pm call with Harmon on June 10, but when she noticed the cocktail of over-the-counter and prescription medications weren’t doing the job, the killer mom grew frustrated and told her mother: ‘We need another option.’ 

Police also examined Sarah’s chilling internet search history, which included ‘searches about medication reactions, the effects of insulin on non-diabetics and the Utah court system,’ Rabbitt said. 

Other searches she made were ‘Where is the most fatal place to be stabbed,’ the chief said. 

The police chief also revealed that Gavin, who was repeatedly stabbed with a knife, also had a defensive wound, ‘indicating that he attempted to protect himself during the attack.’ 

Sarah and Amy shared their final text exchange around 8.40pm on June 10. Their conversation took place about an hour before surveillance footage caught Amy visiting a nearby gas station. 

The grandmother then returned to her apartment, according to Rabbitt. 

The children and two women were found dead in the home after a neighbor requested a third welfare check after the family was last seen 13 days before. 

Investigators recovered electronic files, including text messages between Sarah and Amy (pictured) that explained how the mother and daughter would get medication and kill the children to ‘protect them,’ police said

The children and two women were found dead in the home (pictured) after a neighbor requested a third welfare check after the family was last seen 13 days before

During the two initial visits, officers did not enter the apartment, Rabbitt said. 

Their bodies were so decomposed that it was hard to identify the victims at first. 

An investigation into the horrific tragedy remains ongoing, as the children’s final toxicology results have yet to come back. 

When they do, Rabbitt said they likely won’t be shared with the public because authorities are fearful others might replicate what Sarah and Amy did.

‘Amy Steadman and Sarah Myers consistently portrayed these murders as a way of protecting the children,’ Chief Rabbitt said. 

‘Whatever they believed justified their actions, the deliberate murder of four children cannot be described as protection.’ 

Brady previously revealed that he had received 10 letters from Saratoga County Child Protective Services, notifying him that the agency was investigating the living conditions at his children’s home.

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

Munchausen- by-proxy is a serious mental health condition and a form of child abuse that sees caretakers, often mothers, make up fake symptoms or cause real symptoms to make it seem like their kid is sick. 

Sarah the children’s dad, Brady Harmon (far right), of domestic violence , but he has denied any wrongdoing and has not been charged with a crime

An investigation into the horrific tragedy remains ongoing, as the children’s final toxicology results have yet to come back

Brady said a therapist concluded at the time that Myers was negligent in her care of the children, but they were not in any danger.

‘Nothing happened after that,’ the now-grieving father 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 has since been rescued by Mechanicville Housing Authority management and has found a permanent home.

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

But he believes officials at Mechanicville City School District may have alerted the agency, as the letters stopped coming once Myers pulled the children out of the district in 2024 to be homeschooled.

The Daily Mail contacted Brady for comment.