Days after a Texas mother and her newborn baby mysteriously vanished, her boyfriend has issued a tearful plea for their safe return.

Heidi Broussard, 33, was last seen around 7:30 a.m. on Dec. 12 when she dropped off a child at Cowan Elementary School with her 2-week-old daughter, Margot Carey, in tow, authorities said. The two then returned to their Austin apartment after the 7:30 a.m. trip but “have not been seen or heard from since,” according to police.

Broussard’s boyfriend and the newborn’s father, Shane Carey, begged authorities and neighbors on Sunday to help search for them.

“She’s a great person. She needs to be back,” Carey told Fox7 on Sunday, alongside his father. “I don’t know what else to do—it’s already the third day and it’s getting scary. Not knowing what to do is the hardest part. I don’t know where she’s at, I don’t know if she’s suffering. I’m helpless, and that’s the worst feeling in the world.”

Carey said he last heard from Broussard—with whom he’s been in a relationship for over a decade—at around 8 a.m. on Thursday. When he returned from work at around 2 p.m., he said the house was empty and Broussard’s phone was off, but he “thought nothing of it at the time.”

It wasn’t until he picked up his son at school that afternoon and noticed Broussard’s car door had been left unlocked that he began to worry, he said. Carey explained that he called the police at around 7:30 p.m. after learning that no one had spoken to the 33-year-old mother all day.

“We’re all stumped because everything’s over here—the car’s over here," Carey told KVUE on Sunday. “There’s no signs of struggle. There’s nothing, no evidence, so we’re just trying to piece it together but there really are no pieces.”

“I just don’t see why no one heard any screams or anything out here so we’re trying to put the puzzle pieces together,” he added.

The Austin Police Department confirmed to The Daily Beast that a missing person’s report has been filed for Broussard and her newborn. Broussard’s mother told KXAN she is traveling from Louisiana to help with the search.

Carey said that he has been “going through dumpsters” looking for clues and told CBS Austin he even went to a T-Mobile store in an attempt to retrieve her phone records.

“I just want her to come home,” Carey said, adding he is ignoring the increasing “scrutiny” surrounding him in the wake of his girlfriend’s disappearance.

“She’s amazing. She’s missed. She has her whole family here supporting, praying for her to come home, and hopefully that’s just—I don’t know—somebody to bring her home safe. I don’t care, just drop her off.”