On the morning of Dec. 12, Heidi Broussard dropped her 6-year-old son off at his Texas elementary school. In the car was Broussard’s infant daughter, 2-week-old Margot.

By 7:30 a.m., the young mother and her baby had returned to their home in Austin, according to police. Then they disappeared.

“Something happened,” Broussard’s mother, Tammy Broussard, told NBC News earlier this week. “She would not just leave.”

It would take seven days, an interstate investigation and the help of federal law enforcement to find Broussard and the baby, bringing a grim close to a mysterious case that captured the nation’s attention.

This week, information from authorities’ probe — which included video surveillance and interviews with friends and family — led police to a “location of interest” about two hours away in a Houston suburb. There, authorities found Broussard and a baby matching Margot’s description. The infant was inside the Harris County home and alive, authorities said. Broussard was dead, stuffed into the trunk of a car parked outside, police told the Austin American-Statesman.

The Austin Police Department did not respond to a request for comment from The Washington Post.

On Dec. 19, law enforcement arrested a suspect who was charged with two counts of kidnapping and one count of tampering with a corpse. At a news conference, police would not identify the person they arrested, saying it could interfere with their investigation.

But soon, those close to Broussard were naming the suspect as the young mother’s longtime friend, 33-year-old Magen Fieramusca. Travis County Sheriff’s Office records show that Fieramusca was booked into the county jail Dec. 20 on the same charges authorities listed at their news conference. Her bond was set at $600,000.

Records show that Fieramusca may have also gone by the names Magen Humphrey and Maygen Humphrey, which was first reported by the American-Statesman and confirmed by The Post.

Caressa Nolte, a friend of Broussard, learned that police had swarmed the home northwest of Houston during a live interview she was doing with a criminal justice podcast. The podcast hosts, listeners and Nolte were trying to find a link between the Houston-area home and Broussard when they made a startling connection. The homeowner was listed on several baby registries with Maygen Humphrey.

“Oh my God,” Nolte said, explaining that she, Broussard and the woman she later heard was a suspect had all met as children at church camp. Nolte said she had been talking with Fieramusca “every day” about the case. Fieramusca had told Nolte she had given birth to a daughter, Luna, who was 15 or 16 days old — about the same age as baby Margot.

On air, Nolte said that Fieramusca was Broussard’s “best friend.”

Later, in an interview with the Today Show, Nolte said she was “disgusted” to learn Fierasmusca was a suspect in the case. “I was heartbroken. I was shocked,” Nolte told the Today Show. “I didn’t expect this.”

Nolte did not immediately respond to a request for comment from The Post.

Tim Miller, of the search-and-rescue organization Texas EquuSearch, told ABC 13 that Broussard and Fieramusca had been close friends for at least a decade.

“Magen was there when Heidi had the baby,” he said. “That’s how close of friends they were.”

The Harris County Institute of Forensic Sciences, who didn’t immediately respond to a request for comment from The Post, officially confirmed that the body found in Houston was that of Broussard and that she had been strangled, according to several news reports. Police said they were doing a DNA test to confirm the identity of the baby, who was in the care of Child Protective Services.

“I wish we had completely good news today, but I am proud of the efforts that have taken place here,” said Travis County District Attorney Margaret Moore.

Austin Police Chief Brian Manley told reporters that other charges may be filed in the case.

Authorities are looking for other people who may have been involved in Broussard’s death, the American-Statesman reported.

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