DALLAS, Texas — Learning you've lost someone close is never easy. It was in June when Savanna Gibson discovered her sister had been murdered -- stabbed to death by someone and left in a field near the Trinity River.
"Me, my mom, and my sisters--we were on a group FaceTime, and we were all crying together," Gibson said. "I thought my heart left my body. Just screaming, crying -- we all had to catch our breath."
Cherish Gibson, 25, was found partially nude by police on June 24 in the 200 block of Sante Fe Avenue.
Gibson is originally from Compton, CA, and was visiting Dallas per her sister. Investigators with the Dallas Police Department said Gibson was a prostitute.
After she was killed, another woman was found stabbed to death on July 15 near the location where Gibson was found.
That's when the metroplex discovered that the Dallas Police Department was looking at a potential serial killer. On April 22, weeks before Cherish was killed, 60-year-old Kimberly Robinson was found stabbed to death in the same area.
The department warned potential sex workers because Gibson and another victim were prostitutes.
Shortly after that warning, 25-year-old Oscar Sanchez Garcia was arrested and charged with the murders. Phone data, surveillance footage, and DNA from sexual assault kits were used, connecting him to the crimes.
WFAA asked DPD detectives if Garcia was being looked at for other unsolved murders, but a spokesperson wouldn't comment on the ongoing investigation.
Gibson told WFAA that learning her sister was the victim of an accused serial killer was another shock she wasn't expecting.
The two were close before Savanna Gibson got married. Photos and the memories they hold now mean more to her than they ever did.
"She was funny, she was goofy, she was understanding, and she was always there to talk if you needed her," Gibson said. "That's what I'm going to miss the most: the real, true person she was."
The killings shouldn't be lessened either because some victims were sex workers, said Gibson.
"These are regular people. They're normal people. They have lives, and they have families. They have kids," Gibson said. "We shouldn't judge them by what they choose to do. The decisions they make and the things they do with their lives."
The Dallas District Attorney's Office hasn't announced how it will present Garcia's case to a grand jury -- but Gibson is asking they seek the death penalty.
Intentionally taking a life during another felony, such as kidnapping, burglary or aggravated sexual assault, is a crime eligible for capital punishment.
"I've seen his mugshot," Gibson said. "He looked at those women as if they were nothing. That's how I look at him. So, I do wish the death penalty on him. He doesn't deserve to walk this Earth."
Garcia is an undocumented immigrant and is currently on an immigration detainer.
He was arrested before the killings in mid-March on a family violence charge. A Dallas County Sheriff's Office spokesperson said Garcia didn't come into the jail on any immigration detainer and bonded out.
On Monday, July 31, a Dallas police spokesperson confirmed to WFAA that the department didn't notify U.S. Immigration and Customs Enforcement when they arrested Garcia for beating his girlfriend on March 13.