Heidi Broussard's murder is now a Lifetime movie. Here's the true story behind 'Stolen Baby.'

The brazen and tragic case of an Austin mother being killed and her friend kidnapping her young baby has been adapted into a Lifetime movie.

"Stolen Baby" tells the story of longtime friends Heidi Broussard and Magen Fieramusca, who shared with with each other that they were pregnant at the same time and wondered if they would give birth on the same day, according to court documents. But in truth, Fieramusca had lied to her friend, and instead planned to kidnap her friend's baby and present the child as her own.

The Statesman reported extensively on this case back in 2019 and earlier this year when Fieramusca was sentenced. Here's the true story and who has been cast in the Lifetime movie.

Heidi Broussard and Magen Fieramusca were friends for years

Two decades prior to the murder, the two met at a church camp as teenagers and were very close, according to other camp attendees interviewed by KHOU.

As their friendship continued, Broussard would refer to Fieramusca as her "bestie" in Facebook posts, including when she was pregnant in 2013. By 2019, when Broussard shared news of another pregnancy, her friend suggested she was also expecting.

Police said that lie was part of an elaborate hoax that included setting up fake baby registries.

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Suspicions grew after birth of Heidi Broussard's baby

When Broussard gave birth to her third child that November, her family noted Fieramusca acted suspiciously, going so far as to interrupt the newborn's first meeting with her grandfather. A friend at the hospital noted that she also clutched a pillow over her stomach, pretending to be pregnant at the hospital

Fieramusca also spent that night at Broussard's apartment despite saying she had planned to leave to return to Houston that night.

Shane Carey, Broussard's fiancé and father of the new baby girl, gave her a key to their home. According to Statesman reporting, she promised to leave it on the counter but Carey never saw that key again.

An eight-day search and the murder of Heidi Broussard

On the morning of Dec. 12, Broussard dropped off her child at Cowan Elementary in South Austin and was reported missing with her infant daughter by Austin Police that same day. Officers later testified that a neighbor of Broussard's told them that she saw Broussard and Fieramusca hug outside Broussard's Austin apartment, then saw Broussard get into Fieramusca's vehicle with her infant.

Carey made pleas for the public's assistance in locating both of them after they disappeared.

"I don't know why anybody would ever harm or touch these two beautiful women together," he told KVUE.

Dig deeper: Tips, witnesses led to suspect in Heidi Broussard kidnapping, affidavit says

The search continued for over a week, with more agencies becoming involved. By Dec. 20, authorities in Houston said Broussard's body was found in a duffel bag in the trunk of a car outside a home. Inside the home, was Fieramusca and young Margot.

Fieramusca was arrested and initially charged with kidnapping, evidence tampering and later, capital murder. According to an indictment, she asphyxiated Broussard by “ligature strangulation, with a leash and with her hand.”

How Magen Fieramusca's ex-boyfriend Christopher Green inadvertently alerted authorities to the whereabouts of Heidi Broussard

Before the murder, Fieramusca told her ex-boyfriend Christopher Green she was pregnant with his child. The two still lived together even though their relationship had ended. Green said he had not seen her belly grow, either and while noting the two had a rocky relationship, according to Statesman reporting at the time.

He came home one day in December to find her with a baby on the bed.

"She's been really distant with me about that stuff. I don't know why," he told a Texas Ranger after being asked where the child was born.

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The Ranger had the conversation with him in the parking lot of a Target, where Green had bought baby formula. He and Fieramusca had named her Luna, but the possibility that she may belong to someone else spurred him to encourage law enforcement to take action.

"Sir, is somebody going over to get that baby?" Green said. "If she's capable of this, please go get that baby."

Law enforcement responded to the home, detaining Fieramusca for hours while they waited for warrants, later testifying they took action when they due to believing she was a threat to the child.

What happened to Heidi Broussard's baby?

Not even a month old when she was kidnapped, Margot Carey was initially taken into custody at Fieramusca's home in Houston by Texas Child Protective Services.

Once her identity was confirmed by authorities, she was reunited with Carey and Broussard's family.

Magaen Fieramusca sentenced to 55 years in prison

Just more than three years after Broussard's death, Fieramsuca was sentenced to 55 years in prison after pleading guilty to her murder. The sentence was a result of a plea deal between the Travis County district attorney and Fieramusca's defense attorney.

'Stolen Baby' cast features Emily Osment, Anna Hopkins

Anna Hopkins plays Broussard in the film and Emily Osment portrays Fieramusca.

How to watch 'Stolen Baby: The Murder of Heidi Broussard'

Part of Lifetime's "Ripped from the Headlines" series, "Stolen Baby" will premiere at 7 p.m. Central Time on Saturday, Sept. 23.

The movie will be available to stream on Lifetime's app the following day.

This article originally appeared on Austin American-Statesman: Heidi Broussard murder: How Magen Fieramusca killed friend, stole baby