A Texas woman charged in the kidnapping of her childhood friend who was later found dead was trying to pass the woman’s newborn baby off as her own child, a report said.

Magen Rose Fieramusca, 33, told her ex-boyfriend that she had given birth to a baby on Dec. 12 and he was the father, according to police documents obtained by a local NBC affiliate.

The baby was actually birthed by Heidi Broussard, who was found dead in the trunk of a car at Fieramusca’s Houston home on Dec. 20, according to the probable cause affidavit obtained by KXAN.

“Magen Fieramusca presented Heidi Broussard’s Newborn Child as her own to her boyfriend,” the affidavit said.

Broussard, who was childhood friends with Fieramusca, vanished with her baby Margot on Dec. 12.

Cops later found the mom’s body inside the car trunk — and the baby was found inside the home, unharmed, according to multiple reports.

An autopsy determined that the mom’s death was caused by “ligature strangulation,” officials said.

Fieramusca was arrested on Dec. 20 and charged with kidnapping and tampering with a corpse, but hasn’t been charged in the killing of Broussard.

Austin Police Chief Brian Manley has said “there could be additional charges filed in the case.”

Before arresting Fieramusca, Texas Rangers approached the ex-boyfriend as he was buying baby formula and showed him a flyer with Margot’s photo.

“That’s the baby in my house,” he replied, according to the affidavit.

Fieramusca told her ex-boyfriend that she had the baby at a birthing center the same day that Broussard and Margot went missing, the affidavit said.

Fieramusca’s attorney, Brian Erskine, said in a statement to the outlet that his client is innocent until proven guilty.

“The cursory information contained in the recently released probable cause affidavit is nothing more than mere allegations,” said Erskine.