She helped her 'best friend' give birth. Then she stole the baby and passed it off as her own.

Magen Fieramusca is facing charges for kidnapping and tampering with a corpse. Photo / Washington Post

When she learned that Heidi Broussard's water had broken, Magen Fieramusca jumped into her car and began the 265km drive from Houston to Austin.

The two women had known each other for a decade, and Fieramusca wanted to be there when her "best friend" went into labour.

She made it to the delivery room in time to hold Broussard's hand and help her through her contractions, becoming one of the first people to hold newborn baby Margot Carey on November 26.

Then, prosecutors say, she hatched a plot to kidnap her friend's baby and pass it off as her own.

According to court documents released on Monday and first obtained by the Austin American-Statesman, Fieramusca, 33, had been nursing a fake pregnancy for months. Two weeks after Broussard's friends and family gathered around her in the delivery room, the young mother vanished. Her body was later found stuffed in the trunk of a car behind Fieramusca's home.

Fieramusca, whose attorney has asked the public not to rush to judgment, has been charged with two counts of kidnapping and one count of tampering with a corpse. Prosecutors say she could potentially face additional charges "up to and including capital murder."

As the Washington Post previously reported, Broussard, 33, left home with 2-week-old Margot in tow early on the morning of December 12.

She dropped off her 6-year-old son at his elementary school, then returned to her Austin apartment complex. But when her fiance, Shane Carey, got home that afternoon, both Broussard and the baby were gone.

A week later, Fieramusca was arrested.

Frequently described as Broussard's "best friend," she had met the young mother roughly 10 years earlier, when they both attended the Texas Bible Institute in Columbus, Texas.

Though the two women lived in different cities - Broussard in Austin and Fieramusca in Houston - they stayed close and regularly spoke on the phone, Fox 7 Austin reported. When Broussard got pregnant in early 2019, Fieramusca announced that she, too, was expecting a baby. She wondered if they would give birth on the same day.

By November, when Margot was born, Fieramusca claimed to be 37 weeks into her pregnancy, with her due date one week away.

But some acquaintances were skeptical. Vickie Shreves, another close friend of Broussard's, told People that Fieramusca didn't look that pregnant when she turned up in the delivery room, and kept a pillow over her stomach.

Carey, who told police that Fieramusca appeared "visibly pregnant," nonetheless found some of her behavior odd.

When Margot was handed to her grandfather for the first time, Fieramusca interrupted and said that she wanted to hold the baby first, the affidavit says. Though she claimed that she was going to have to leave soon, she spent the night at the new parents' apartment instead of driving back to Houston.

Carey told police that he gave Fieramusca a key, which she promised to leave on the counter when she left. The couple never saw it again.

On December 12, the day that Broussard and her daughter disappeared, surveillance cameras captured a car that resembled Fieramusca's driving toward the back of the couple's apartment complex, the affidavit says. When Carey returned home that afternoon, he found his fiancee's car in the parking lot with its door unlocked and her purse inside. He also noticed that she didn't seem to have taken any of the baby supplies that she would need for an outing with Margot. Hours later, Broussard still hadn't returned, and none of her friends or family could tell him where she was. Carey called the police.

While officials launched an extensive search for the missing mother and child, Fieramusca returned home to Houston, where she had been living with her ex-boyfriend, Christopher Green. The pair had broken up in March 2019, around the same time that Fieramusca told him that she was pregnant with his child, Green would later tell the authorities, according to court records. They continued to share a home, and Green watched as Fieramusca's stomach expanded. When he touched her belly, it felt hard, he told the police. But because they were no longer a couple, he never saw her unclothed.

Then, on December 12, Fieramusca told Green that she was going to the beach with her cousin while he was at work. According to the affidavit, he didn't see her again until the following day. When she returned, she had a baby with her. Begging Green not to be mad, she told him that she had gone into labor and delivered their child without telling him.

Nearly a week later, on December 19, Green went to buy baby clothes and formula at Target. As he left the store, detectives from the Texas Department of Public Safety intercepted him and handed him a missing persons flier with pictures of Broussard and baby Margot. "That's the baby at my house," Green allegedly responded.

Investigators headed to the former couple's home. Inside, they found a baby girl, who DNA testing later confirmed was Margot. According to the affidavit, a gray Nissan Versa was parked in the small backyard behind the house, as if someone was trying to hide it. Emanating from the trunk was the "unmistakable odor of decomposing flesh." The smell came from a black duffel bag that contained Broussard's body. She had been strangled.

According to the affidavit, Fieramusca had Googled "Heidi Broussard" at least 162 times during the five weeks leading up to her arrest. She had also searched "reasons for Amber Alert" and "Amber Alert issued Austin" on the day her friend disappeared, before an Amber Alert was issued. When questioned by police, Fieramusca said that she had recently had a baby at a birthing center in the Houston area. But she couldn't remember the name of the birthing center, and she claimed that no one besides the nurses and doctors had been there when she went into labor.

It's unclear whether Fieramusca was ever actually pregnant. The affidavit notes that the FBI's Behavioral Analysis Unit found her to meet the profile of someone who would kidnap a child out of "maternal desire," which can apply both to mothers who have lost pregnancies and those who have lied about expecting a child.

In a statement to local media outlets, Fieramusca's attorney, Brian Erskine, noted that her defense team has not yet been given the opportunity to review the evidence in the case. "We call upon patience and resisting the rush to judgment until all the facts are in." he said. "The cursory information contained in the recently released probable cause affidavit is nothing more than mere allegations."

Now a little over a month old, Margot spent several days in foster care while her identity was being verified, but was reunited with her father shortly before Christmas, KHOU reported.

"We're a very tight family - full of love and we just want to try to get that going again," her grandfather, Ty Carey, told the station. "This has been the bizarrest thing that you can ever imagine in your life."