Councilman Joe Carchio, who is supporting the event, will be out collecting signatures on Saturday.
Carchio said he is behind anything that will help stop other parents from having to endure the pain that Chelsea's parents felt.
"I think if we don't stop it right now and take a stand....more young girls will be in the position that Chelsea's in," Carchio said.
Robin was running late for her ballet class and was lured into a stranger's car in 1979. Two weeks later, her skeletal remains were found in the woods of Sierra Madre.
Chelsea was killed by John Albert Gardner III, 31, a convicted sex offender who pleaded guilty to her murder and that of another girl April 16, the Times reported.
Robin was murdered by Rodney Alcala, a convicted child molester and rapist of a 15-year-old girl.
Alcala was later found to be the serial killer responsible for the death and rape of four other women by the time he offered to give Robin a lift to ballet class.
Girls like Robin and Chelsea are the reason Shaw is working to get Chelsea's Law enacted.
The law would lock up violent sex offenders for life after the first offense, add lifetime GPS monitoring for felony sex offenders, and make it a misdemeanor for sex offenders to loiter in parks where children play, according to the proposed bill.
Child predators can't be rehabilitated, Shaw said. There is no cure, so there should be no second chance, she said.
"Existing laws should be reviewed, improved on and new laws made in order to fill any loopholes that allow perpetrators to get off," she said.
Shivers crept down Shaw's spine when Robin's kidnapping was reported on TV. Since then, she has been passionate about protecting children.
"Robin's death could have been prevented, had the system worked," Shaw said. "Her face is forever etched in my mind, as is Chelsea's.
"The system is broken," she said. "It needs to be changed."
If You Go What: Super Signature event to raise support for Chelsea's Law
When: 10 a.m. to 1 p.m.
Where: Albertson's at 7201 Yorktown Ave., and Fitzgerald's Pub, 19171 Magnolia St.