A devastated father is seeking $400 million from New York authorities after his four children were k*lled in what investigators described as a planned m*rder-s*icide.Brady Harmon has filed a legal notice accusing the City of Mechanicville, Saratoga County, two school districts and a housing authority of failing to act despite years of alleged warning signs involving his children.His 17-page filing claims the children were repeatedly mistreated, drugged, and medically mishandled before their passing on June 10.Harmon had been preparing to reunite with his children just weeks before the tragedy.A heartbroken dad revealed that his three children were supposed to spend the summer with himBrady Harmon/FacebookHarmon had not seen his children in person since 2019 because of a bitter custody dispute with his former wife, Sarah Myers.The four children were Harper, 13, Hudson, 11, and 10-year-old twins Gavin and Gracelynn Harmon.According to Harmon’s legal notice, that was finally about to change. He had reached an agreement for the children to spend the summer with him in Utah from July through September.As he prepared for their arrival, he said, “I sent their flight information. I planned activities based on their interests.”He also asked for their medical records, medications, allergies, doctors’ information, and other paperwork required under their parenting agreement.“I believed I was preparing to welcome my children home,” Harmon wrote.Brady Harmon/Facebookpariott7SheIsBack2023He spoke with the children on June 7 and was looking forward to seeing them.Three days later, however, Myers told him the children were sick.“The kids have gotten a little stomach bug, throwing up. Is it okay to switch your online visit to tomorrow at 4 pm your time, please,” she wrote.Harmon said he responded that he hoped they would feel better.When he tried to contact them again the following day, nobody answered.Investigators now believe the children had already been slayed.The police shared that the children were drugged before they passed awaySarah Myers/FacebookAuthorities said 44-year-old Myers and her mother, Amy Steadman, carried out the slaying on June 10 before taking their own lives.Investigators believe the children were drugged before Gavin was repeatedly stabbed.Police Chief Bill Rabbitt later said investigators uncovered messages between Myers and Steadman discussing the children’s medication on the day of the ki*lings.“Sarah Myers instructed Amy Steadman that the medications should be administered between 10.30 am and noon so they could be finished before a scheduled telephone call at 6 pm with the children’s father,” Rabbitt said.Investigators also found a message in which one woman wrote, “It’s not working. We need another option.”Police said Steadman had visited several pharmacies in the days before the passing.Amy Steadman/FacebookAkaBerrier63413NotTrum47765844Investigators also found internet searches involving medication reactions, what insulin does to non-diabetics, and the Utah court system.Another search reportedly asked, “Where is the most fatal place to be stabbed?”Toxicology testing later detected kratom and diphenhydramine, the active ingredient in Benadryl, in the children’s bodies.“Preliminarily, there is nothing in the toxicology findings that has surprised investigators or is inconsistent with the direction of our investigation,” Rabbitt told WNYT.The children and the two women were not discovered until June 23, when a neighbor called 911 after noticing a foul odor at the family’s Mechanicville apartment.The heart of Harmon’s legal notice is his claim that the June 10 slaying did not happen without warningAmy Steadman/FacebookHarmon’s filing accused Myers and Steadman of ab*sing the children for years and alleged they were regularly given substances including melatonin, Benadryl, and kratom.The notice described this alleged behavior as consistent with Munchausen syndrome by proxy, a form of ab*se in which a caregiver fabricates, exaggerates, or causes illness in another person.Harmon also claimed Gavin was subjected to particularly serious treatment.According to the filing, he was “falsely diagnosed with several mental illnesses” and given psychotropic medication that allegedly made it harder for him to resist.Brady Harmon/FacebookOne incident in particular has become a major part of his allegations.In May 2024, all four children reportedly became ill while attending the Mechanicville City School District.Three were taken to Albany Medical Center with symptoms that the filing said were consistent with an op*oid o*erdose. Gracelynn allegedly became so sick that she required Narcan.Myers reportedly blamed Benadryl.The hospital contacted Child Protective Services following the incident. Harmon’s lawyers argued that the episode should have prompted much stronger intervention, including removing the children from their mother’s care or launching immediate criminal and ab*se investigations.His filing also alleged that the children’s increasing absences from school were attributed to homeschooling while information about their education, medical treatment, and alleged ab*se was withheld from him.Harmon claimed this happened despite his parental rights.Another major allegation concerns what happened after the June 10 slayingsmusiclablover52GageLastma45691Harmon claimed he repeatedly requested welfare checks on the family while the children were still inside the apartment.According to the filing, police did not enter the home until June 23, after a neighbor noticed the smell and called 911.By then, the bodies had badly decomposed.Investigators later found letters inside the apartment. One was a handwritten confession signed by Steadman, while other unsigned writings were believed to be by Myers.Those writings accused Harmon of ab*sing Myers and the children during their time living in Utah.Harmon strongly denied those allegations.Brady Harmon/FacebookHis legal notice instead argued that Myers used accusations against him to gain sympathy and resources and to maintain control over the children.Harmon has previously called Myers the “culprit” rather than a “victim” and accused her of using the children as a way to continue controlling him.After their passing, he wrote, “My children were not pawns to be sacrificed when control was slipping away.”He continued, “They were four beautiful human beings with personalities, dreams, fears, laughter, and an entire family waiting to love them.”Harmon’s legal notice names the City of Mechanicville, Saratoga County, two school districts, and the Mechanicville Housing AuthorityBrady Harmon/FacebookHarmon’s attorneys argued that different agencies had opportunities to intervene before the children passed away.The housing authority is included because it oversaw the apartment complex where the family lived.Harmon’s lawyer, Nicholas Liakas, specifically criticized Child Protective Services for its handling of the earlier complaints and investigations.“Child Protective Services failed these children,” Liakas told the New York Post.“When the warning signs are there, people need to step up. We can’t wait until a tragedy occurs to say what should have been done before these children are ab*sed.”The legal notice is seeking $400 million, but filing a legal claim does not mean that amount has been awarded or that the allegations against the named authorities have been proven in court.Liakas also said the case is about more than financial compensation.“What we’re doing is we’re seeking justice for this family, but we’re also trying to implement institutional change here,” he said.“This is horrifically sad,” wrote one netizen