The 34 year-old was captured on grainy, black-and-white surveillance video. He was alone and was wearing shorts and a t-shirt.
UNSOLVED: Evidence doesn't talk
He walked out of frame and seemingly vanished.
[Ads /]
"When I come out here, It's like I'm back to the very first day that somebody knocked on the door," Steven's mother, Jessie Hebert, said as she stood at the gas pumps along Dayton's Highway 90. "I can't go forward. I'm still right here."
Steven was Jessie's first-born son. He was the goofy one who loved to draw, play guitar and spent night after night on his Xbox.
Steven was happiest alone, Jessie says.
Jessie and Steven were close. She still has her favorite letter from him in a frame that was sent when he was off at basic training.
It's signed, "Love, Your Little Soldier."
RELATED: Woman wanted in Louisiana man's mysterious disappearance may be in Houston or Katy
Steven spent a year in Korea before moving back home to Dayton.
"I would give my last breath just to have one more day together," Jessie said.
Steven had rented a small trailer across from the gas station where he was last seen. Police believe that's where he was coming from shortly before he went missing.
Investigators found his car, keys and wallet at his place. Days later, they found his cell phone in the grass behind the gas station.
It's important evidence -- If only Dayton police detective Terry Dale could get into it. Without Steven's phone password, she's locked out.
Thanks to a search warrant, Dale was able to pull Steven's call history, but the text messages are what she wants. Texts could possibly reveal who Steven planned to meet or where he may have been going.
"You think about it all the time. You want to get their child back to them," Dale said. "I have four kids. I can't imagine what it's done to them."
[Ads /]
In the weeks after Steven disappeared, Texas EquuSearch and law enforcement searched most of Dayton.
Volunteers walked the woods, used ATVs, drones and horses to comb through rough terrain. Dale said she searched abandoned buildings and houses all around the gas station.
"Whether he's four or 34, he is still her child, and he is missing," Texas Center for the Missing's Melissa Rangel said. "Someone knows what happened to Steven Dean."
Rangel and her team are pushing Steven's case back into the spotlight during this weekend's "Missing in Harris County Day."
The event on Saturday is aimed at bringing families in or around Harris County together that are missing a loved one. You can file a missing persons report, no matter how long ago your family member disappeared, and submit your DNA to national databases used by law enforcement to track down families of those missing.
"We have to stay hopeful. It's all about being hopeful," Rangel said.
All it takes is one tip -- One person who saw Steven that night to come forward.
[Ads /]
The gas station video and Steven's cell phone are the best two pieces of evidence detectives say they have.
Dale admitted, it's not much and it's not ideal though.
Jessie and her husband are not certain that it's really their son in the video. He doesn't walk like Steven, they said. But, Dale said two of Steven's friends who talked to him that night saw him at the gas station, though their meeting doesn't happen on-camera.
Dale said the female friends told detectives that Steven seemed a little on edge and said he was high. Still, that doesn't explain disappearing.
As we approach two years of Steven missing, Jessie says she won't ever stop looking for him.
"If we stop, if we give up, I give up on him. I can't do that," she said.
If you know what happened to Steven Dean or if you saw him that night, call Dayton police at (936) 258-2130.
"Missing in Harris County Day" is happening Saturday, Aug. 7. A virtual event is planned from 10 a.m. to 3 p.m. and all families and friends affected by the disappearance of a loved one are invited to participate. For more information, visit the Texas Center for the Missing website. Families will also be able to file a missing persons report with police over the phone and attend virtual panels.
You can now binge the "Unsolved" series on Hulu. You can also watch live newscasts and in-depth reporting from ABC13 on your favorite streaming devices, like Roku, FireTV, AppleTV and GoogleTV. Just search "ABC13 Houston."
For updates on cold cases and the latest on the "Unsolved" series, follow Courtney Fischer on Facebook, Twitter, and Instagram.