GALVESTON, Texas (KTRK) -- On Halloween 30 years ago, the life of then 10-year-old Maria Gibson was changed, as she was putting on her costume to go trick-or-treating.
"The phone rang, and my sister started screaming. My aunt had been killed," she said.
Sylvia Salinas was the strongest person she knew. "She was so tough and wasn't scared of anyone," Gibson recalled.
Salinas was fatally stabbed in her family's Galveston food store during a robbery. Her parents had left for lunch minutes before.
The cash register had a built in alarm that was triggered.
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Police arrived four minutes later, but the robber was gone and Salinas was dead.
"She knew who killed her, because whoever did was standing behind the counter next to her. She would never let anyone she didn't know there."
Galveston police released the original crime scene video taken by investigators last year, which shows the store, the empty cash register, and two weapons under the counter.
"She had a machete and a loaded gun," Gibson said. "And they were never touched. She knew that person."
The knife the killer used was also left behind. Gibson is hopeful that DNA can be extracted through new advanced methods to finally identify the murderer.
She speaks to Galveston detectives once a month, and places flowers on her aunt's grave often.
The family still circulates flyers asking for information at cold case events held in Galveston. She has never forgotten her.
"As long as we're alive, we won't stop looking for that person, even if they're too old to be around anymore, they're going to have to answer to God for what they did. If they don't get punished on earth, they'll get punished in the next life. I guarantee that," Gibson said.
Anyone with information is asked to call Galveston police or Crime Stoppers at 409-763-TIPS (8477). You can also submit a tip online at www.Galveston.CrimeStoppersWeb.com.