In 1986, a newborn wrapped in a red sweater was found abandoned in the bathroom of a fast-food restaurant. Nearly three decades later, the baby is all grown up and looking for her biological mother, and tens of thousands of people are trying to help.

Katheryn Deprill began her quest on March 2 by posting a photo on her Facebook page in which she held up a sign that said, "Looking for my birth mother. … She abandoned me in the Burger King bathroom only hours old, Allentown PA. Please help me find her by sharing my post."

Deprill, a 27-year-old married mother of three, figured the photo would be reposted by friends, maybe friends of friends. A week later, it’s been shared nearly 27,000 times by Facebook users around the world. Deprill’s story is rocketing around the media world, too.

But there’s still no sign of the mystery woman who left her in a restaurant bathroom.

Deprill, an EMT who lives outside Allentown in South Whitehall Township, said there’s so much she wants to tell her birth mom.

"Number one is, I would really like to say, ‘Thank you for not throwing me away, thank you for giving me the gift of life, and look what I’ve become,’" Deprill said Monday.

She’d like to know her family medical history, as well. And she has so many questions about the circumstances of her birth and abandonment.

"What made her do it? Why did she feel that she shouldn’t leave me at a hospital? Was she going through a horrible time?"

Deprill learned about her abandonment as a 12-year-old, when her sixth-grade teacher assigned the class to a project focusing on the students’ family backgrounds. Deprill came home and demanded answers from her adoptive parents, Brenda and Carl Hollis. They slid a scrapbook in front of her that held newspaper clippings from 1986.

The articles explained how a Burger King patron had heard a baby’s cries and discovered Katheryn on the bathroom floor. How a restaurant worker then called police. How police were trying to track down the mother.

"I comprehended it, but it still didn’t sink in that it was me, that a mother could just lay her baby down and walk away. That is just mind-blowing to me," Deprill said.

She launched her search with the blessing of her parents. In fact, it was her mother who suggested holding up a sign and posting it on social media.

Deprill said she is "definitely not looking to replace my brothers and sister nor my adoptive parents, because I’ve had the best life. It was the best childhood ever."

At the same time, "I would really like to see somebody who looks like me, and maybe I have (biological) brothers and sisters. … I’m really frustrated. I just wish I knew more about her."

Some people have told Deprill that her birth mother is unlikely to come forward for fear of being prosecuted. But Lehigh County District Attorney Jim Martin said there’s a two-year statute of limitations on child abandonment.

"Even if that were not the case," he said via email, "I believe most DAs would exercise sound discretion and not prosecute someone under these circumstances."