Family members of a missing pregnant teacher from Montgomery County are offering a $25,000 reward to help track her down.

Laura Wallen disappeared last week and has not been seen since.

Police found Wallen's truck abandoned in an apartment complex off of Gramercy Place near Columbia Mall last Thursday.

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Investigators are not saying what they found inside of Wallen’s condo or in her car.

“Pick up the phone,” Mark Wallen said “Whoever might be helping and hiding her, please come forward and make it happen.”

“I know we're all trying to do everything we can to find her. I just pray that-- I pray that she's safe, she comes back. That's all I care about right now,” Tyler Tessier said.

The Wilde Lake High School teacher never showed up on the first day of school, and the last time family members heard from her was in a text message on Labor Day.

Wallen's boyfriend, who she's known for 10 years, said she is four months pregnant and excited to have a baby.

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She showed no signs of anything being wrong and has never disappeared before, he said.

“If somebody has her, please understand that you've taken away a huge person in so many people's lives,” Tessier told reporters at a press conference.

Police have not found evidence of foul play and don't know what led up to Wallen's disappearance.

Detectives are looking through surveillance video, searching her computer, and waiting on permission to look at her cell phone information.

“It's one of the hardest things a father can do is have your child taken away way, way too soon,” Mark Wallen said.