INSIDE A DAUGHTER'S DESPERATE SEARCH FOR HER MOTHER 17 YEARS AFTER SHE DISAPPEARED, AND HER DETERMINATION TO BRING HER KILLER TO JUSTICE, ON "48 HOURS: THE DAY MY MOTHER VANISHED"

Nicki Myers Bates was just 7 years old in 2006 when her mother vanished and the man her mom lived with told police he watched her die. That man, William Greer, went on the run, evading authorities for years. Nearly two decades later, Bates is still desperately trying to find her mother's remains. Bates talks with 48 HOURS correspondent Peter Van Sant about her mother's disappearance and about bringing her killer to justice in "The Day My Mother Vanished," to be broadcast Saturday, May 11 (10:00-11:00 PM, ET) on the CBS Television Network, and streaming on Paramount+.

"It takes a lot to not let it consume me," Bates tells Van Sant about her determination to figure out where her mother's killer buried her. "I try to focus on my kids and my husband, but they will tell you I'm determined ... If I just have free time at home, I'm on my computer, looking at maps, looking at old, you know, areas, what they looked like then and what they [look] like now."

Bates' mother, Tammy Myers, went missing in December 2006 near Houston. Three days later, the man Myers had been living with, Greer, was found half-naked and intoxicated on the side of a road. He was recorded on police dashcam video saying, "The gun just went off ... the worst thing I ever did was look in her eyes and watch her die."

Greer was arrested for public intoxication, but without probable cause to believe that there had been a murder, police had to let him go. By the time investigators did find evidence, Greer was gone. He traveled from state to state, and over a decade later, he was located in Mexico. Myers' body has never been found.

"He's definitely among the worst," says retired U.S. Marshal Leslie Ramin, who investigated the case. "He's an evil murderer."

But without a body, could prosecutors get a conviction?

Van Sant reports from Houston on the complicated case, which has several stunning turns. He's also there when over two dozen volunteers help Bates search for her mother in a wooded area Greer said he may have buried her in.

Bates says she longs for a resting place for her and her family to pay their respects to her mother. "I'm just trying to stay hopeful for myself, but also for my children," Bates says, "I don't want to give up."

Judy Tygard is the executive producer of 48 HOURS, which is broadcast Saturdays at 10:00 PM, ET/PT on CBS, and streams anytime on Paramount+. You can also watch 48 HOURS on the CBS News Streaming Network Wednesdays at 8:00 PM, ET. 48 HOURS is also available on CBSNews.com, Fave TV, Pop TV, Pluto US, Pluto UK, Pluto Nordics, Pluto Canada and Pluto South Africa. Download the CBS News app on your phone or connected TV. Follow 48 HOURS on X, Facebook and Instagram. Listen to podcasts at CBS Audio.