A 24-year-old Illinois woman vanished during a trip to Chicago with her boyfriend — and he came home without her. Alyssa Smith hasn't been seen since Sept. 30, and her mother is living every parent's nightmare while the system moves at its usual pace.

Rebecca Smith told Fox News Digital the family is "going through hell." Her daughter's sisters are waiting at home. The flyers are up. The posts are circulating. And the boyfriend, Jacob Ray Caso, returned from Chicago alone.

"He has changed his story a couple times, so I'm a little confused," Rebecca Smith said. She added that she had previously had "a great relationship" with Caso.

Caso has not been accused of any crime or wrongdoing. His mother told Fox News Digital he has returned to the Chicago area on three separate occasions to search for Alyssa. He reshared a missing persons poster on social media with the message: "Time to come home. No one is mad at you."

The Palatine Police Department says detectives have been "actively investigating Smith's whereabouts and following up on information received regarding possible sightings." Reports indicate Smith may have been seen Saturday, Oct. 3, in the Grant Park area and near Cicero Avenue and Roosevelt Road. Investigators are working to verify those sightings.

Smith is described as a White female, approximately 5'5", 135–140 pounds, with brown hair and brown eyes. She has several body piercings and numerous tattoos — notably a "Pennywise" clown tattoo on her left shoulder. She was last believed to be wearing a gray hooded sweatshirt, light khaki-colored pants or sweatpants, and white Adidas sneakers. Her social media indicates she works at Chipotle.

"We want to get the word out that if you see something, say something," Rebecca Smith said. "Call 911."

A young woman goes missing with the last person seen with her — and that person walks back through the door alone, story shifting. No charges. No arrest. Just a mother begging the public to look for her daughter. Whether Caso knows more than he's saying is a question for investigators. Whether the system treats a missing 24-year-old with the urgency it demands is a question for all of us.

Anyone with information on Alyssa Smith's whereabouts should contact local law enforcement or dial 911.